[Tremelune]

Very doable. One route would be to buy a Nissan Leaf, adapt the motor to the gearbox (tricky/custom), and use the batteries, charger, BMS, and other bits as much as you can. That's probably $10k.

Another route would be to use Chevy Bolt batteries and a Hyper9 or some such. Adaptation would be a lot easier, and the batteries are much better, but you're looking at $20k minues what you could recoup form selling the rest of the Bolt.

I wouldn't mess with the brakes or steering until it seems necessary. With regen, you won't use the brakes much at all, and heavy steering has a lot more to do with tires and castor than weight. The torque from the average electric motor will be more than stock.

That said, building the Bug with a kit will be a lot easier, teach you quite a bit, and would probably have better resale than a home-spun conversion. Still smells like a $20k proposition, if I recall EV West's prices correctly.

No conversion is a weekend project, but any means.

 

[Tremelune]

The Leaf has been hacked quite a bit. I believe the current state is that, with a $1,000 controller, you can use the motor, charger, DC/DC converter, and BMS (if you use the full pack in the same configuration). With the Bolt you're looking at figuring out controlling the motor, and then a few grand worth of DC/DC, charger, BMS...I don't think much of the Bolt has been figured out because they're new, but I haven't really been keeping up.

The Bolt batteries are stronger and more dense. You don't need to use all of them, so weight/space is more or less what you can swing. Same with the Leaf, if you buy $1,000 BMS system. Drivable Leafs can be found for near $5k. Most Leaf packs you'll find are 24kW. Batteries lost capacity rapidly until March 2013. They got even better in the 2015 model year.

There's no slam dunk, you just need to choose your compromises.