think I need some help this time , moral support really more than spanner wizardry
Stick with it Lee. Many people - including me - wouldn't have the skills to even start a rebuild like that. Best I've managed is a Honda CB125 - I doubt I could even get an engine out of a GTA.
I've had two professionally rebuilt engines - one in a Mk II Mustang and one in a Lotus Excel. Both went BANG within a few hundred miles. Even the professionals don't always get it right.
Third time lucky - go for it - plently of moral support from the club