If it was my truck I would just bite the bullet and order factory body mounts, that way you'll have the piece of mind that they are correct heading forward.
Before you start moving things around I would measure the existing distance across the top of your door openings on both sides and record...
From my past experience, I would check your body mounts.
If your body mounts are worn out or half new, half old, trucks been taken apart ETC you'll have a hard time getting the proper body panel gaps. If possible I'd get the truck level on jack stands and replace all the body mounts with a new...