Stevieturbo, my last reply was meant for you mate, got my wires crossed!
and yes steveboyslim incl vat the cost would be nearer £7k.
Thanks to Paul RS as well.
I have just recently had my car into AET Motorsport at Normanton (very impressed)for a turbo upgrade and chip/ remap etc after I fitted some new pistons/followers/valve springs and now have about 50bhp more power, so what I may do is run the car for the coming season with its existing T5 box and think about a gearbox upgrade for winter 2015.
That way I can see how she goes with one upgrade at a time, then if regs permit do the box next year. This should give me more time to make the choice! Although I havent got too much time as I am now 68 !