I have a running 540", i am swapping the cam.

I pulled the motor and pulled existing cam out. The new cam will not slide into the engine all the way. It stops at the last cam journal. I am sure i can force it in, but it will not slide in. I tried putting my orginal cam in and it slides in just fine, all the way in. Tried the new cam again, and it stops at the same spot, about 1" from being installed.

I have read all about how cam bearings can do this or that once installed, but they all address new engine builds where the cam does not fit. Not a running engine and a cam swap.

What do I do?

Is it a bad cam?