I'm building a 56 F100.....Mustang II front suspension....narrowed (3") Explorer Differential....springs under frame. Going to use stock pick up be & fenders.....would like to run 18's all the way around....anyone done something similar and do you know what the back space on the wheels you bought was? Any help would be appreciated. Thanks. George

 

I used the following on my 56
front wheels- 15x7 3.75 backspacing Crager SS
front tire- 225x75 R15 Firestone
rear wheel- 15x8 4.5 backspacing Crager SS
rear tire- 255x70 R15 Firestone (wheel well is 11" tire is 10" width)
These were with a Heidt's MII in front and with a 91 Ford explorer 8.8 rear-end
The front backspacing I got from a tech from Heidt's.