You might want to do some research on the crank, you don't mention the year but many Schwinns of the 70s (Varsities, Continentals etc.) had the once piece Ashtabula cranks that have a very proprietary bb, I believe they can be converted to square taper but it takes a special kit anyway it might be a bit more work than you are thinking, I am sure someone here has actually done it, or you can read about it
here. I believe Ashtabula is Greek for
Boat Anchor. Good luck with the project and post some pics
The 73 SS below has the one piece crank -it weighs a ton
