I NEED ANSWERS FOR MY NEW LEAF CELL CONVERSION.

WARNING!!--If you disconnect, or completely switch off, the VECTRIX battery, initial reconnection must be done thru a current-limiting resistance, to protect the capacitors in the motor controller, as they charge! If this is not done, eventually, ( perhaps immediately, even!) these capacitors will suffer damage from the very high charging surge at time of connection. A 2 stage connection process is needed, where initially, connection would be made by a small relay, thru a resistance of perhaps 1000 ohms @ 10 watts, followed about 1 second later by the direct connection, shorting out this resistance, to enable normal operation. Be Careful!

marylandbob is right, you can do it with a two step reconnection procedure. Failing to do so every time you want to wake up the vectrix, these capacitors/fuses will be damaged.

http://visforvoltage.org/forum/11047-2x-chargers-unprogrammableunflashable#comment-71856

As they said, about the battery disconnect/reconnect. I don't think you need to do that, to be honest. I barely see any voltage drop on mine when it is off and just sitting in the garage. When my charger failed, I had to spend 2-3 weeks without plugging in. It of course failed after I had discharged the battery, riding the day before and only had voltage in the upper 120V when I last shut down. Incidentally, while just sitting off, rather than drop further, the voltage climbed a few volts above 130V and stayed there.

On the 24 cell BMS leads: yes, install them all. You will have some of them unused later, of course. Make sure you don't short whatever wires you connect to them - voltage is high and the amps are strong: can burn/kill. Also, measure carefully which wire goes where - the pins are not necessarily in the same order as the cell terminals.

And yes, you can balance charge/discharge at low currents through these.

Here is what mine looks after connecting to the battery and routing to the seat storage area. The orange wire with white plugs is the 24-cell BMS leads from Hybrid Auto and are attached to the cells. The black leads are also from them - they plug in the orange ones and take the wires to the seat area where I have terminated them with plastic 9-pin connectors (5 of them).

I use five 9-pin R/C style connectors to which I can attach a small R/C style 8 cell volt meter (plug it in each of the 5 connectors and measure 8 cells at a time, or use 5 voltmeters at the same time). I don't keep these v-meters plugged in permanently, just if I want to check the battery from time to time. Or I can measure the voltage of any cell or the whole pack with my voltmeter. Or plug the female half of these 9-pin connectors and those can be connected to a R/C balance charger to balance charge up to 8 cells in parallel (or if you have them, plug 5 such chargers to balance charge all cells in the whole pack in one shot)

to which I can attach a small R/C style 8 cell volt meter (plug it in each of the 5 connectors and measure 8 cells at a time, or use 5 voltmeters at the same time)

These voltmeters failed to give accurate voltage readouts.
What's more, during any ride they get plenty electric noise from the system, giving tremendous false readings, beeping the alarm continuously: they can read 1,99v and 4,55v from a real 3,00v cell. Have a look a my testing video:

http://youtu.be/gd8VV6oT7LU

The only one that works fine enought is this cell logger:

Yes, these $2 a piece v-meters are junk. You can turn the alarm feature off (but I think they don't remember the setting between uses).

I don't keep them plugged in al the time. Out of 6 that I bought, only a couple have 4-5 of their 8 channels fairly accurate. The others are less good. They are consistent though - may measure higher or lower on the different channels (vs. actual) but will do so the same way over and over. Anyhow, I was not sure what to expect from them, bought them, and my conclusion is they are no good for use during riding, but are OK to check voltage when stopped (and because they are so small, I can have one in the glove compartment in case I want to check the cell balance somewhere on the road).

Voltage from the same cell will vary during a ride - based on the up to 6-7V voltage drop I see at full throttle at high speed (vs. low speed steady), I calculate cell voltage anywhere from 3.7-4.1V is normal change over a second or two. And that is what I see on the display, which is "smoothed" - so the momentary changes could be bigger.

At the end, I just use the 9-pin connectors that I intended for these cheap R/C meters to directly measure the voltage with my multimeter (and to eventually, down the road, balance individual cells if needed).

When freshly charged, all my cells are within 0.02V (at 4.1V or so average). When measured just after a ride, they were all within 0.09V at about 3.5V average. So, they do discharge sligthly differently, apparently. Yet, they seem to charge to about the same values... Still, even a 0.1V difference is not huge and because I am leaving a healthy margin on both ends of the charge/discharge, I don't think it is an issue (I don't have a BMS). Granted, I have no idea how the voltages differ during hard acceleration, which is where it matters to have balanced cells, but I suspect no cells get too stressed as I'm not depleting them too much in use...

I'll keep an eye over the next few charge/discharge cycles to see if the small disbalance that I have now increases or not. But the weather is getting too cold to ride much, so solid conclusions may have to wait until Spring.

Yet, they seem to charge to about the same values... Still, even a 0.1V difference is not huge and because I am leaving a healthy margin on both ends of the charge/discharge, I don't think it is an issue (I don't have a BMS).

Some cells have slightly diferent internal resistance. In the end, as months go by, one cell will be less charged or overcharged than the rest, and your safety margins will vanish, killing that cell. Depending on how smart you are at detecting that cell failure, you may prevent a potencial fire.
I use MINIBMS, it does the job. But now I'm recomending Emus BMS with bluetooth adapter. Pretty exensive, but fully programable, comes with android app, it displays many parameters, interestingly it can display ALL the cell voltages/temperatures in your tablet or smatphone:

https://play.google.com/store/apps/details?id=eu.elektromotus.emusbms.evgui.blue

By the way, I'm planning to upgrade to the EMUS, so I'm selling 40 new, boxed 40Ah GBS cells with my 40 distributed MiniBMS sensors and central BMS unit, everything for 1500 Euros. If anybody plans to upgrade a Vectrix to lithium with a bms at that bargain price, send me PM or e-mail.

Some cells have slightly diferent internal resistance. In the end, as months go by, one cell will be less charged or overcharged than the rest, and your safety margins will vanish, killing that cell. Depending on how smart you are at detecting that cell failure, you may prevent a potencial fire.

It is important to monitor the individual cell voltage and capacity. I read a post at Endless Sphere about the Leaf cells, which stated they "self-balance". Would be interesting to see over time if that is indeed the case, but I am not counting on it.

Without a BMS but with periodic checks for the cell balance, the only danger is a catastrophic failure of one cell while charging or discharging - that would go undetected until it is too late and will be really bad if it happened! Other than that, no BMS is fine. That is because the Leaf cells appear to be of good quality and are well matched to each other, so they have similar capacity and internal resistance (at least while still fairly new). So, when used within a healthy margin, well below 100% capacity, there shouldn't be any problem for quite a few charge/discharge cycles without the need to rebalance. I'll probably add a BMS down the road, but for now I'm hesitant to spend the big bucks on a good one and a bad one is probably riskier to rely on than none at all...