Hey guys just to let you all know that the main gear is way worse than first thought. Put it up against a new one and there isn't much left lol.
The teeth were all pulled to one side but what's happened is I then turned the diff around to run rear mount, and it has tried to turn the teeth back the other way. So note to self.

When we go from forward mount to rear mount we are changing the way the teeth run back to front from forward mount to rear mount. So that's why it finally got that noisy cause it wore the flat top parts off the teeth.

So if u want a smooth drivetrain from front to rear mount engine it's best to have two main gears so one will run in one direction and the other to run the other way.
Cheers
Fordy