I had the same thing with the Bobcat's.

...Not really a problem.


Enlarge the opening slightly, and when you glue or screw the well into place, push it down and in.

This forces the walls to conform to be a bit steeper.

You can also CAREFULLY hit it with a heat gun and press it into place as you do so.

But you must be VERY careful not to overheat the plastic and the temp variance is fairly small where this occurs.