I draw the line at refrets, but am more than happy to do anything else on a guitar. I think the key to learning is don't rush, and don't do anything you can't undo until you know what you're doing. Also be aware that a major screw-up can be really expensive to put right, or result in a guitar that's only fit for spare parts.

I'm currently trying to decide on what pickups to fit to replace the stock models on my Tele.