If the F model and the J model are the same frame why don't the instrument panels fit? I've gotten the bug again to totally upset the apple cart and build my F. I am in so deep I already know what I got and if I can turn it into a J and build it for top speed then I am looking for donors. But I am having trouble looking for similarities that would cross. Or does one have to strip down to the frame and build new? Just trying to get my head wrapped around it. My goal is to build a super cle