I agree with Norstar. I mounted an Edson on my stern pulpit as you can see in the photo below. I wanted it to hang plumb, so I fabricated a short piece of starboard as a standoff between the cleat and the Edson.
This required I obtain some longer hardware - 18-8 SS Flat Head Phillips Machine Screw 1/4"-20 Thread, 6" Length, from McMaster Carr.
I didn't want the hardware to protrude on the back side, so I countersunk it as you can see below.
I can get my Mercury 6hp 4stroke up there manually, but would love to have a crane someday.
Here is the link to Edson.