trophy900

Hello I have just bought a 349 mark 3 in bits.I have managed to rebuild most of the engine but im not sure how to line up the gear selector mechanism to the selector drum.What position does the drum start from and how do all the marks line up.Managed to get a parts book but there are no descriptions on how to set up the engine or ignition timing.If anyone knows where to get a proper workshop manual or could give me some advice on the above it would be much appreciated cos im dying to get on the thing. cheers.