From the shop manual on this page:

http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0103.htm


Floor panel cross support to frame rail at rear = 49/64” – 53/64” (.765”-.828”)


Bottom of floor to top of frame at front mount location = 1 53/64” to 1 57/64” (1.828” – 1.890”)


Use your frame as a jig for the other dimensions and make sure the pedal’s won’t rub. There is no set dimension for running board to rocker as a rubber “skirt” hangs down from the rocker to fill the gap. The paint and body forum are your best bet for these questions. Try the search feature for “floor replacement”, “patch panels” or ”cab mounting”.

1952 1300 Canadian 1/2 ton restomod
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