I'm gonna go with a complete frame ie. (Fatman set up). I'll just pull my cab off n sell the whole rolling chassis motor,trans and let somebody thats restoring a truck or something use the original stuff.
A word to the wise, hold on to the chassis until you are finished with the build. You WILL find things on it you don't want to buy and things you can't buy from vendors that you will need before it's all said and done.