I picked up some stainless steel 8-32 screws and self locking nuts. The machine screws that came with the compass would most likely have worked fine, but fine never did it for me.
Here’s the fit up.
Mounting holes drilled.
I figured that having screw head in the forward hatch was better than the threads and nuts ripping at every dry bag I’ll ever put in there. I put a ring of marine sealant around the screw heads and inserted them up through the recess mount. Then I put another ring of sealant around the top. In this case more is better as I don’t want water in front hatch if I can help it.
The finished product.