Hi Roger, the engine which I had fitted 6 months ago is out and completely stripped down. I think you are correct in saying that the thrust bearing has protected the crank. Unfortunately, where the engine had been stored for so many years with the rocker springs under tension, 2 of them had disintegrated without me realising and the metal splinters have gone through the engine, hence the rebuild. New bits include, camshaft, springs, main and thrust bearings, some valves and rods. Also, the aluminium racing fly wheel had warped and needs replacing. I am hoping to have it all back together in time for Silverstone later this month, but it's looking unlikely.