I have a corbin super ace, vintage...already built out, from the very early 80's. It was built with an OS 40 4-cycle. of that error. I still have that engine, but this plane is incredibly underpowered with this engine. This engine is installed to wooden rails, using blind nuts etc.

The current positions of the blind nuts are 8mm x 42mm

I have checked and an OS 56FS. It looks like it will fit the cowl, however the mounting bracket holes are

8mm x 44mm

Wonder if I can 'force' this to fit, or if i need to completely rework this mount configuration.

Trying to do this without 'carving up' the current configuration of the engine houseing and cowl etc.

Any other advice...