I know the topic of conversion kits has been beaten like a dead horse. The ATI kit is the only known .40 conversion for the gap and the be honest the .40 ammo is just as expensive as .45Gap. Just pondering other ideas and possible options. Being as how my tactical solutions .22 conversion kit will fit my 37 as well as a 17 and a 22. The upper just slides right on to my 37 frame, could I possibly swap slides to a 17 with 17 mags? I guess what I’m asking is are the internals of the frame the same? What’s your thoughts?