Larry Seecamp made .45 1911 conversions in the '70's. I have a Colt Commander Seecamp I carried while a Belmont cop, and about 10 other guys carried them also. The PD's were just starting to converto to autos from revolvers and we wanted something we knew had stopping power (In those days most cops were ex-military). These were the first DA/SA .45 autos around, and they work great. Don't know the value as I'd never sell min.

Tom