Marlin Bolt Actions -One Piece Scope Base
There are multiple ring position location options on the one piece base. Usually the problem is the front ring location to compensate for where a shooter wants the scope for ideal eye relief. I found that as long as your objective of your scope is not huge it isn't a big problem. Larger objectives may require taller rings to obtain the clearance needed. The included scopes in the Marlin rifle packages are not very good. I am being nice just calling them "not very good".