Not sure. Most of the twin bar Schwinns had the two mid bars run from the downtube to the seat-tube, then stop. Here's an example:
The one year, the twinbars continued past the seat-tube to become the seatstays, like your frame above. The other style wasn't made for a very longtime, either. I've seen these frames marked as Tornados, Typhoons, Skippers, and Flying Stars. May have been other "models" as well. Middleweights, sometimes with 2speed rear hubs. Personally, I think your frame is nicer than the red/white one I've pictured above, but they're all cool frames.
The Typhoon used that frame for just it's first year, while the other models as mentioned above used that frame for a few years. Hopefully that red paint is all there under there if you want to make it shiny. Does the chain guard say Typhoon? It's my second favorite Schwinn frame, after the king size cantilever frame offered for just a couple years on a couple models, 20" instead of the standard 18" seat tube.
The tires are Westwinds. Good usable condition too. I like the frame but the whole package doesn't do it for me. Do you think it should be kept original?
IMO it's no longer original being painted like that. You could probably remove all that paint and reveal a nicely protected paint job but maybe not too. Bottom line is, it's your bike. Enjoy it how you want to.
Way cool bike. I have had both a 26" & 20" version over the last couple years. They have moved on to new owners now.
Agreed, it's yours and should be the way you like it. As for value, even though the quality is good, there's not demand for these bikes even in original condition, maybe $100 or so. You can't buy a new bike anywhere near that quality, and American made, for that money. I still hope classic bikes catch on, and everyone will have to have one as a new trend. Then they would sell for a good price. That frame will look good any way you work it. I painted my friend's Jan 61 Skipper and he wanted apes, so that's how it sits. 2.125 tires fit with no modification.