Actually, the mod here recommends shaving one of the tabs and says his is too tight.
Another thing that will help you enjoy Blitzwing is to shave a bit off of his backpack tab. It's that tab in between his shoulders that snaps into the backpack, and on mine it fit too tightly in the slot. Rather than feel like you're going to break him every time you transform him from bot mode, take a razor blade (or sharp instrument of your choice) and lightly shave a bit from the sides of the tab. Be careful, and just barely do it as it doesn't take much.