I like the Open Revolt t-shirt.
What is it you're looking for — series? parallel? through-the-road?
I think the easy route would be a mild hybrid using a Buick/Impala eAssist altermotor. See here.
https://ecomodder.com/forum/showthre...tml#post536957
No powertrain mods, minimal battery requirement like Ecky suggested at #13.
edit:
...and teoman at #5.