Mono leaf front suspension, is what your describing, popular on T's and stuff but, from what I'v read, too light weight for a truck, if your lucky, you could find a '40 Ford clip and graft it on, although, what your saying makes no sense to me at all, you have a '29 Chevy 4dr woodie? or is it just the wood that's under the body they used for support? and you want to use an old cracked, hacked up frame just to hack up some more so a old 30's truck cab and box will fit, explain with detail, someone will help. What I would do myself, if the '29 was in fact a woodie, it's not worthless but, worth more to a restorer because it may be quite rare, that and, I'v seen and heard that to get the wood reproduced, it's gonna cost 30k, unless you know how yourself, the frame sounds like trash. If the body just has the wood reinforcement, and it's rotted, that's normal to find, just replace it and box and enshure safty in the frame, get the '40 Ford front clip, a Buick nailhead V8 and a 3spd manual, and an old rear end that will work with that, bolt it all up and paint it flat black, I don't like true rat rod cars, but, I know the concept.