Crunch from 2nd to 3rd and from 4th to 3rd. Also gets stuck in 4th!

How about picking up a 2nd hand box... gonna be a couple of hundred max

 

Yes, I was thinking about this option but if its coming out I might as well make sure that the 'box going in will be a good one and also last for a while. A used one could be a bit risky i guess.
I have 5 rib 2ltr 'box and thought this was a good gearbox and worth keeping, especially if I go for more power in the future

 

5 rib is 1800 box actually.