Sorry, Ink, but I can't see that happening. I am unaware of what kind of experience you have with people, but the ones I have seen that are around the age of sixty and above and even some a bit below ofttimes complain about some sort of aching. Their bodies just aren't young enough. Even my former P.E. teacher, who is in perfect shape by the way, is having difficulty with his kneecap.
And, if you were to think about it, being at the age of sixty two would be considered a true elder, if we were to presume that people in general don't live as long as we do.
I believe you should think more on how the character would fit and develop in the story. Maybe you should make him ten years younger? What kind of relationships and position are you planning to give him?
EDIT:
Rayn Night said
I have no doubt he would be the best qualified to do it xD That is not really what I meant. Guardians are (to my belief) exclusive to the Tower. Skye is from Ferros, which is now disconnected from the Tower since they made the new one in Valeal. That's more the story I want to know :P
This is a very good point. I presume that some mages and guardians would have retreated with the Archmage on their own accord. It is quite logical to give them the free will to chose where their loyalty lies. The majority would have probably stayed with the Tower, since they give an oath to not bend their knee to any country after completing their training, but the patriots and those who still harbor some feelings would surely have taken the Archmage's side.
I'm quite curious about what kind of position Ferros' Archmage currently holds at the Tower, figuratively speaking. Is he labeled as something similar to a traitor? A feral mage? Surely, he's scorned in some way, yet he is probably held with high regards at the same time.