Ralley wheel questions

So what all came on factory cars? Im thinking about putting some on my 68 cuda that is now BBP, what widths were there for 14 and 15 inch and witch weels and tires will fit with my early B rear end and 75 duster discs?

In my experience, the 14 inch versions came in 5, 5 1/2 and 6 inch widths. The 15 inch rims were 6 and 6 1/2 wide.

15x6.5" and 15X7 in 4.5" bp only from factory

If your rear axles are re-drilled 4" flanges, and still using small pattern re-drilled drums, then you may have problems with bbp rallyes.