I have recently put the front panels together on my 46 1/2 ton stepside. I found many misalignment problems, but solved them all by loosening many of the bolts holding it all together, then pushing and pulling till everything lined up. The top stay rods running from the firewall to the radiator support frame have a large influence on all this. Also, sit the hood in place, to get an idea of relevant gaps. Loosen the cab mounts if you need to. The cab may be out of square to the chassis. These old trucks are very flexible in the body work, so you will be surprised where an inch of movement can come from. Gaps and measurements are the clue, usually.
