apex and forgestar wheel backspace help

[CamaroJesse]

Ive been on the hunt for a quality but affordable wheel. I may have narrowed it down between apex wheels or forgestars.

http://www.apexraceparts.com/apex-products/wheels/#.VV-s8flVhBc

http://www.forgestar.com/v2/wheelsf14.php


I have seen a few 1st gen f bodys with these wheels on them but i cant find info about backspace or rear end widths. This is for a 67 firebird. Im in the process of buying a new rear end and im wondering if i should go with stock camaro or firebird length or even go wider? Im wondering because of the lack of dish on these types of wheels. I do not want to run adapters. So im just trying to figure out a good rear end length to go with to make sure that these wheels will fit with the available offset without adapters.

thanks!

[TheJDMan]

If you plan to buy a rear end anyway, I would recommend buying the wheels and tires you want first. Once you have them you can mock them up under the car and get an exact measurement from the wheel mount to the opposite wheel mount for your rear end width. That way you have an actual measurement and you are not guessing about the rear width.