re-fitting the gear box and find that the rear gear box mount holes don't line up with the holes in the "horns" (is there a proper name for these?), the horns are about 4-5mm too close together which explains why it took so much force to remove the bolts, is this a common problem and except for jacking the horns apart while I fit the bolt is there another method to achieve the result of bolt holes lining up, preferably permanently.

is it the factory gearbox cradle (mount) ?

I think so, was on the car when I bought it but it has been painted or powder coated, any way to tell if it's factory?

Sometimes you just have to bite the bullet and go for it, jacked up the box and put a scissor jack between the horns, jacked it out till it fitted (actualy went a bit too far and had to pull it back in a little) now all is good , fount that I had a broken gearbox rubber mount white I was at it so off to get a cupla newies.