Like Don said, if your truck was titled using the engine number AND you still have the engine in it that it was titled to, you're good to go. If it was titled to the engine and that engine is no longer in the truck or it was titled to the unit serial number you probably have (or will have) some hoops to jump through.
The id plate or "vin" is all i have from id plate inside door. There is no engine id number. And the original engine is in my storage. I will simply put the old id tag on the new cab.Should not be any hoops, i don't think. Side note everything i purchase i get signed receipt even if its on notebook paper.Hopefully it will keep me out of trouble.