Unless you took the nut/bolt loose that holds the flywheel and didn't retorque it properly you didn't change the flywheel timing. Did you set the air gap between the new ignition modules and the flywheel properly. On some engine the flywheel magnets stick out just slightly further than the rest of the flywheel. and if you don't set the gap with the magnet facing the ignition modules they will bind on the flywheel when attempting to start.