Got a chance to get some info and pictures of current setup.. As rmay635703 so kindly pointed out; this is a bit overkill. But I could work with those numbers.
What's the weight of the Leaf motor? I just read that the current AC-motor is only 4kW, not 6-7kW as I thought. Yes, physically the Leaf motor is somewhat larger, and it's probably some kilos heavier too, but that's just obstacles to overcome.
Current AC-motor:
TEC TECA2-112M-2-B35
Current VFD will be replaced, but it's called Emheater EM9-G3-004 if anyone is interested. It's currently controlled by PWM with a base Hertz of 2kHz according to the Smoothstepper plugin in Mach3. What kind of signal does the throttle pedal on the Leaf generate? Is it a standard potentiometer of some kind? And what about forward and reverse signals? Found a small film on youtube made by Paul Holmes last year showing off some kind of aftermarket control board for the Leaf-inverter, but I can't find any more info on it. Feels like that would bring stuff in the right direction, but I might be mistaken.
Thanks for now.