me and my mate have just done a rebuild on my cos and up to now we have had it down at santa pod q-mile and then fitted a t34 and 500 cooler and dark greens and all the rest that goes with it, then put it on the roling road and got 350bhp at the wheels, done 4000 miles and it is still going strong. i think it was an easy job as long as you ar prety handy on the tools but i saved my self £2500 on the price i had