My friend, an original PowerSport partner, built several all aluminum engines. They always used multiple mounts. The problem was always the studs, and the fact that the rotary has the problem of uneven heating. Powersport attacked that problem by changing the cooling system on their Superlite engine with the water input in the center of the combustion area. The flow was outward to both ends and out. The standard engine uses a series flow which is okay for automotive levels. If you have ever seen the internals of the sideplates you will see how much baffling Mazda did internally to get a fairly uniform heating across the housings. Studs still need to be improved for continuous high power use.

 The conical mount for the Lyc is supposed to be focused at or near the center of mass, engine and prop, for smoother running. The mount added to the Mazda will need to be laid out differently depending on which PSRU, and prop combination. The center of mass can vary a lot depending on the prop selected and the mass of the PSRU. The difference of mass of the rotary itself can change radically if aluminum side plates are used. (about 1/3 less) There are a lot of variables to consider just to use a standard aircraft engine mount. I believe it's much easier to use a bed mount and save the engineering for a better PSRU and perhaps a drive for a variable speed prop. (I've attached a page of an original PowerSport article showing the sideplates and assembled engine.)

Bill