RE: another conversion thread. just interested
Ryobis have been through some changes. As you say, the older ones you just unbolted everything and there you had an airplane engine; no cutting involved. Then they made a version that had a one piece case that you had to cut the crankcase out of, and then I have seen some lately that actually have a Homelite 30cc in them! I also have at least one that has a completely different engine that I don't recognize at all. Just looking at the exterior it looks like it will be a fairly easy conversion, but I haven't had time to pull it all apart and see how good the ports are, etc.
AV8TOR