After being delayed in work for 3 hours extra today I had to readjust plans to replace the oil pump. So thought to my self why not strip it and have it ready for the new pump and rebuiling tomrrow. Should only take a an hour or two to strip it down. How wrong was I. Everything come off fine. Except the last bolt. It just happens to be one of the 5mm hex bolts that is situated next to the fly wheel. Slid the hex key in and found that without anything other than turning it with my fingers the head has been rounded off by someone in the past. Anyone got any tips on how to get this out without dropping the gearbox?