Me and my friend are thinking about starting a buisness making custom aluminum parts. Pulleys and such. What parts are in high demand and who wants them?

Hoods, trunks, fenders. :D

Hmm those are to big for me to make. I can make aluminum motor mounts and outher brackets for engine accesories. Also some interior parts like shifter knobs.

Shift knobs...
I've been looking for a decent shift knob forever. I want one the same dimensions as the stock one but with a white and black pattern on it. Like half white, half black leather. If you made a good quality shift knob like that, I'd buy it.