Panel alignment and cab mount spacers

[TXgearhead67]

I need some advice on my 67 stepside. A little backstory first. This truck had severe rust that I cut out and repaired. It wouldn’t surprise me if something’s moved a little even though I braced it. Fast forward to present day. I’m aligning body panels and having trouble. Doors are factory and line up pretty good to the cab. Both fenders are aftermarket and fit like crap. Having to slot top front bolt holes on back to get a bolt to go through. Driver side fender is overlapping door at bottom. Passenger isn’t to bad to the door. I have new cab mounts and mounted the rear with a 3/8” spacer to get what I got. I’ve swapped the mounts around thinking I had the mounts wrong but that didn’t help. Radiator support is aftermarket and I am using the 67 mounts for it. My question is how much shim can I put under rear cab mounts without running into trouble. I measure 2 1/2” from top of bed to cab body line right now. I’ve temporarily bolted the front bumper on and can get a finger between it and nose. Cowl sits about 3/8” evenly higher than aftermarket hood. Any help would be much appreciated and I’m not scared to cut and weld. Lol sorry for the long post.