Spicer 5789X u joints

I am a little mind boggled.... Bought Spicer 7260 u joints, they won't actually fit in because the 'meat' in the center of the joint is hitting if that makes any sense?

Does one dremel it a bit so it will clear?

It is a miniscule amount but it will not allow it to go in.

Not talking about the cups, but getting the body of the u joint in place to start