It's an old Santana. Previous owner says "late 80's, early 90's" that's got a solid rear axle. The only way we can reasonably transport it is to remove both wheels and throw it across an "accross the back of the car" carrier. So the wheels will come off regularly.
So.. what would it take (if it can be done) to take the existing rear wheel and rebuild it with a quick-release axle?