Cam install question - HELP!

Ok got a roller cam for my '99 magnum 360, cam bearing were already installed by PO.

Cleaned and lubed shaft and bearings.

Cam slides in easily through all bearings except it WON'T SEAT -the front bearing seems REALLY tight, like tap it in with a mallet tight; so I did

Tried the cam backwards to see if it was just the front bearing that was tight and it does appear to be rather snug - I have to assume the rear is equally snug, or more so, as it WILL NOT turn by hand when "installed"

What to do?