That might be better to do on the actual ramp segments than to alter the road names. Creating road name discontinuity can have unwanted side-effects like Big Detours, though in this case I don’t see an obvious risk. I added W 600 N as an alt-name just in case, and to make it more obvious that it’s intentional.
What about moving the naming back to the ramps as “to westbound 600 N” and “to eastbound 600 N”? That way it’s extra clear and won’t confuse anyone who knows the road is properly “west 600 north”?