A fit physically is what I was referring to. The .72 is my favorite engine, it gets better as time goes on. My decision came after seeing how lightly the Hype is built. I'm sure it would have worked great and been a stupid amount of power (that's a good thing) but I wasn't into beefing things up to handle the torque and cutting things out to clear what needed to be cleared. I'm sure some would argue the need, but I have a tendency to overdo things a bit. But...if you modify the motor mount or get something heftier, and hang the Saito inverted instead of at an angle like the West it would fit well, and appears to look like it might clear the cowl. I ran a Cline regulator with my UCD3D and the Saito 100. I would recommend the same if you go with an inverted 72.

I think your .91 might be a different story though...