Because it's not just the gun on the left arm, I swapped the entire lower forearm out. The right forearm attaches to the gun so much more completely than the left forearm. Doing that, however, doesn't allow the arms to fold up nearly as far as they need to transform him. If you just plug the mechtech gun onto the left arm he'll transform just fine. I've had a lot of people asking how hard it would be to swap the forearms and hands around to make him look more G1. The answer is: it's actually pretty easy if you don't want to turn him into a tank anymore. Ultimately, though, I was just bored at work and trying a few things out.