I have a hinged floor plate model (but it is not a bottom bolt release, it's the older version with the bolt release on the top) and it has a washer between the trigger guard and the floor plate frame. The washer was included with the factory rifle. The washer is .165" thick and the floor plate frame is .155" thick at the tab (same as yours). I think if you add a washer, it would solve your problem. Here are a couple photos to show the washer.

Cody