Hi everyone, 
it's been a while, but I finally got the gearbox out, I've been busy working and setting up my workshop.
anyway, got the box out, sripped it down and found the main shaft bearing in the adaptor plate had been pushed back and cracked the housing causing the selector forks to bind up and grab two gears at once , hence why I couldn't select anything.
I've been looking around for another box but with no luck. 
is there much work involved in putting a 1200 box in?
or does anyone have a 1000 box lying around that they are willing to part with?

I put a 120y box in about a year ago no probs... Like Dave said you just need the cable as well. I had to bash the tunnel a tad where the cable connects to dunno if there was another way around that but very minor.