As a general rule with skew gear drives,mesh the gears approx.....then twist the housing BACKWARD until the timing is correct...TDC at point break will be about right....As its coil ignition.you can use a light or a multimeter if you have one,to indicate point break.......My old grandfather had a surefire method to test spark timing......no,we wont go there, instead thumb over plug hole,crank motor,watch timing light,you cant go wrong,light goes out as thumb is blown off plughole....