I am not familiar with the Millett sight you reference. I will however throw in a plug for the SA tech support guys. When I first purchased my SA 1911 I had a number of questions. I sent them an email one evening, contact info from their web site, and they got back to me with a detailed response the next day. If nothing else they seem to be passionate about their product. It's worth a try.
Age is a case of mind over matter. If you don't mind it don't matter. Satchel Paige