Switching to 5x4 3/4 Lug pattern on a 71'

[Rreemo]

2 questions on this....do you guys know if there are any rotors that will swap over from a car? Someone told me that mid 70's Bonneville rotors will work.

Also, I'm wondering if axles from a Chevelle 12-bolt might happen to be the right length to swap the rears with the truck 12-bolt? I happen to have a set in the garage.

I have a set of GM Ralleys, and I'd like to put them on the 71'....just wondering what is commonly used to convert from 5x5 to 5x4 3/4.

Thanks!