With the motor correctly positioned, see how there's just ("Light Hand fit") enough room to slide the 'foot' of this engine mount through the gap between the legs of the stand and the sump fins. I think it was extremely decent of Rotax to organise that!

I use old Reliant connecting rod bolts to loocate the jig mounts. Their ground shanks give precision locartion in an 8mm drilled hole, clamped with a piece of tube, as seen here. All Voyager owners have a collection of used Reliant connecting rod bolts...