Pleased for you & Charley that the vet check went well.
When Alfie was castrated, although he was only 15 mths old at the time, his recovery was very, very quick. The following day you would never have know he had the op.
It was more the case of watching he didn't touch the stitches
and i don't know if we were just lucky but he never attempted to.
If you decide for sure to go ahead with castration & because Charley is older i would make sure someone is with him for the days afterwards.