As my previous threads have indicated, i cannot get gtx 951 to run. Here is my question. No where in the repair manual does it state or indicate that the number piston has to be on tdc before bolting on rotor cup. But does it? I have spark, compression and fuel. I wonder if i am getting spark at the wrong time. When timing i used the hole in the flywheel with the protrusion on the mag cup. Does it matter where flywheel is at in rotation when cup is bolted on?