I have a model 110S that I am trying to put bases on and I thought I had the right ones but the rear base is considerably higher than the front. My receiver is a "flat-back" type so I went with the Weaver model 46 for the front and a 61 for the rear since that is what I found on this forum and in the Weaver book. I would say that the rear base is about .050" to .060" higher than the front. What gives?

In this photo I have a straight edge laying across the rear base and extending over the front base to give an idea of the gap. Thanks for any ideas