Hello again!
So 3 months later than planned i finally got round to sorting the exhaust. I knew it was blowing somewhere as it gives a nice tinny rasp when you put your foot down. Also, the exhaust has always sat low even after replacing rear. exhaust hangers
Found 2 leaks initially, cat to manifold and a joint on the pipe before the back box.
Got the car on stands and a jack under the cat and replaced the gasket and hardware.
The centre exhaust mount had perished so replaced that aswell.
Whilst i replaced those bits i slackened the rear hangers so that i could attempt to get the exhaust sitting up in the bumper. Got it all centred, couldnt do much in the way of getting the tail pipes up into the bumper.
Tightened it all up and now there is a leak post-cat. Looking at the join there is nothing providing a seal, just a clamp.
Plan now is to disconnect the exhaust from the cat, give that a coat of assembly paste and the same again on the join before the back box.