1980 w/41mm tubes is a fxwg. Not all 41mm tubes are the same. The bottom has a captive bushing in the later tubes but your fxwg tubes do not. There are other differences. Your brake calipers will not bolt on to those lowers. If you find calipers that go with those legs, they will not work with your wheel,disc etc. There are a host of issues, but don't despair nothing money and time can't fix.I have a 1998 dyna fxdl. I recently aquired a wide glide front end I was told was from a 1980 fx ?. Im try to find out if I can use any 41mm tubes that are 24 1/4 .And will my brakes mount up? And any other things i might run into.