Please bear with me as I do not yet have all the components, so this thread is a work in progress. First off I'll start by stating my intention. I'd like to help clear up some of the speculation, misconceptions, etc regarding differences in the P220 9mm and .45, and converting to either caliber on either frame. I have a older non-rail frame P220 .45., serial G 275 XXX, so it's a 220-1 and I believe the serial number puts the manufacture somewhere around '96-98 (correct me if I'm wrong). My intention is to build an "American" P220 9mm using the necessary components from a Euro 9mm in my .45 frame. Why you ask? Because an American P220m 9mm with button mag release is an itch that P226's and P225's just can't seem to scratch for me. What can I say, I like obscure stuff and doing things the hard way. I also plan on swapping the left over .45 parts into the Euro 9mm just for the heck of it, and because I've seen mention of a few others that wanted to do that conversion to their Euro 9mm's.