Speedmaster bezel swap

My 2998-3 has apparently been refitted with a later B6. Dot Beneath 70 bezel. (According to Moonwatch Only the B1. Dot Diagonal 70 bezels were fitted to reference 2998-3 through 145.022-69.) I wanted to make my 2998-3 appear more correct/original so I took it and a 145.022-69 with a perfect B1 bezel to the watchmaker to swap out. I asked the watchmaker to measure the inside diameter of bezels before re-installing. According to his measurements the B6 bezel has an inner diameter of 36.54mm, while the B1 bezel has an inner diameter of 36.45mm. He was concerned about the bezel swap fitting because of this .09mm difference and also stated that the cases appeared to be slightly different where the bezel attached.

Two questions for those that have changed bezels on Speedmasters:

1) Is .09mm difference worth being concerned about either breaking or losing a bezel?

2) Have you noticed this difference of inside diameter of bezel variations (the outside diameter of the B6 bezel is .09 wider also)?