After some recent engine issues, I'm keen to have a system for using my old 6hp 2 stroke Mercury as an aux engine. (It's quite heavy (32kg) because it's the same block as the 8hp (and I think the 9.8) and I plan to upgrade it to 8hp at some stage)
My Osprey has a lip at the top of the transom, curved outwards, about 5cm length. It also has some extra fittings on the transom (crane lift points), so space is tight.
I think I can fit on a chunky aux bracket like this:
Force 4 Outboard Motor Bracket - Only £99.95 - Force 4 Chandlery
However, I wonder whether it might be just easier to cut a chunk out of the transom lip to fit it directly onto the transom? If it could be done neatly, I think it would look ok.
P.S. Those scratches/marks on the inside of the transom are where I managed to jam the auxiliary on when I was in urgent need!