Snake I had a garagist do the same on me, I strongly suggest a new liner with every tube change, and if stuck, wrap some of that fabric like repair tape round the inside of the rim a couple of times.
Outa, I also stripped mine, so what I did was plug the hole with an aluminum weld rod and then I tapped a new hole a little closer to the motor and it works great. It's so easy to strip it's a bummer, a bit like breaking the exhaust studs off etc. etc..
