Did Schwinn use the same shifter on both 3-speed and 5-speed models? Since one was an internal gear hub and the other a deraileur, it seems like they'd need different cable travel. The Fastback that I just picked up has a broken S-A hub and missing the shifter. I was toying with the idea of lacing in a new S-A 8 speed hub, which is geared pretty well for small wheel bikes. I'm curious if the hub could operated with a modifed Schwinn shifter somehow or if I'd be stuck using the twist grip that Stumey Archer includes with the hub. Has anyone looked into that sort of thing before?