Quote Originally Posted by GoktimusPrime View Post
So just enforce a universal head-port size. That doesn't cost any extra money. It's something that HasTak have done since 1984 5mm post. The large 1987 Targetmasters can actually swap weapons with the small 1988 Targetmasters as well as 5mm post weapons from any other Transformers line!
It is the same size. Tight or loose fit is a tolerance issue

Quote Originally Posted by Ozgardian View Post
I can now tell you that there at least 2 different moulds for the Headmaster Units as I ripped of Darkmoon's arms to put them on Nucleon so Galvatron would have a fuller crown but Nucleons ball joints were too big. So I tried Terribull's & they fitted fine. Doesn't look as good with Terribull though, wrong colour.
Sure there could be more than one mold, so long as the dimensions are the same