Hey, Jack, it looks as if the guys you are responding to - who used the Saito 100 - may not be monitoring the thread these days.

You can mount the engine inverted, 90 deg or at the 45 degree angle that has been pre-drilled and blind nuts installed. The 45 deg angle provides for the least cutting of the cowl and positions the muffler to exit in the little channel in the bottom of the fuselage.

I have an OS .91 4c installed in mine, using the stock mount and the 45 degree stock position, and it runs fine. I assume the Saito would also run well in this position. As you can see, all that was needed was a very small cut for the rocker cover.