It's easier than you think. You can go to a salvage yard or battery store ,like Sears, and ask for all their used car batteries. They'll be happy to give them to you. You can also offer to pay a dollor or so more to any customers for the 'core charge' ,that's like a refundable deposit.
Once you take out he back seat of the car, you can stack them all together, then connect tehm all in series, you can lay a sheet of 3/4 thick plywood and lay down another layer of batteries all tied together in series.
If yoou have a winch you can take out thje gas motor, if not strip everything except the engine block out of the engine bay.
I used a couple radial saws with the blades removed to turn the car's wheels, one on each side. When you want to go jsut complete the circuit and your moving. I did it in a weekend, I'll post the video.