After that I cleaned up the water pump and re-installed the pump and cover, and then put the engine back in the frame, while it is still light enough to carry. All three engine fixing points lined up OK, (no warping of the engine cases - phewwww!), so then the gearbox went back in. Had to resort to asking my fellow gamma owners (on the Gamma list), where the 1mm O'ring on the end of the secondary shaft went - so that stopped play, just in time for a lovely ride out on Libby's Street - just to charge the battery you understand!
Anyway the O'ring goes on the outside of the main output shaft bearing, so that was duly put in place Sunday morning, I must have removed the box at least 10 times, due to a number of little problems - first the kickstart mechanism somehow moved, and then I lost the small tab that holds the gearchange barrel in place, in fact it had jammed in the gear change mechanism, - thank goodness the gears would move because I was 2 steps a way from fitting the kickstart and heaving on it, which obviously would only have made things worse! Anyway after all the faffing about, got the gearbox in and tightened up, then I had to fit the rear sprocket, in order to hold the clutch inner basket for tightening, so then I fitted the neutral switch ball and spring (spring goes in first) and the oil pump plate (no pump here), and then the gear lever plate, which was very stiff to fit (hmmmm), and finally the rear sprocket and chain!