I did this axle swap on my Cannondale SM600 of the same vintage as your bike. No issues at all, same lock nuts and axle nuts reused on chromoly QR axles. Easy swapover. Been riding it this way for over 30 years. I wanted a bike I could break down to fit in my little Honda Civic, and could change a flat and fix a breakdown without having to haul around a 15mm and 14mm wrench.