I did have shrinkage issues. One went together OK - the one in the pic above. The other one is being difficult. It still has a good amount of hot glue on the fabric that held the grills onto the cab. This glue was on the back side of the grill, but due to shrinkage is now on the side edges preventing the grill from fitting in the opening of the cab.
If I thought ahead, I could have brought the frames home with me when I washed the fabric and reinstalled the cloth while still wet to prevent such shrinkage.