When I purchased my Retina MBP back in 2012, I had a spare Magsafe adapter from my previous generation 15" (2011) MBP. I ordered one of the adapters along with my RMBP and have been using that older adapter with it ever since. Aside from the cable fraying a bit, the old adapter has been working fine, I think. Would that old power adapter be a 60W or an 85W? I haven't had any issues with it charging, to my knowledge. I'm ordering a replacement Magsafe 2 cord to fix a frayed cord on my newer adapter and was thinking I could do the same with the old adapter since it's frayed as well. Any reason to think I couldn't replace the old Magsafe cord with a newer Magsafe 2 cord on the old adapter?