It's probably going to cost you some decent money to buy the parts to do this. There's a few ways you can go. One would be to switch out the top of the shroud with a cup mounted to the flywheel and re-coil mechanism fixed to that. Look at the later F series motors for this example. Two other ways these were made are having a recoil, and starter gear mounted to the engine block under the side of the flywheel, where your ele start motors are. Some pulled straight up to start, while others had the starter rope routed through eyes and up to the handle. I hope this makes sense. Kinda hard to explain.