I am wondering if there is a difference in lens size.....I would appreciate if somebody could try that out I have only a FMJ frame.

In my experience FMJ frames have lenses that are a little bit smaller. If you look on the lens box for some older frames there will be two sizes of lenses, one for FMJ and one for not. I'll try to find some pictures.

I would always want any lenses for FMJ frames to be a tad smaller. That shit chips if you look at it wrong and taking lenses out of FMJ frames scares the hell out of me.

I ceracoted mine no more chipping. FMJ coat is so cheap. I had carl zeiss lenses custom made but I screwed them up and my old black ones are also a little bit scratched.