I'm trying to get an OS pull start motor with a threaded shaft. However, Tower claims you can't get the RG X with a threaded shaft; only with that pilot shaft that won't work for my application. Is there a way to convert an older motor (OS .21 SE-B) to pull start? How about an aftermarket kit that works with an OS? I really hate that donut start/starter box method of starting- there's gotta be a way to do it.