I had a request to install a compass on the kayak I am currently building. However, it needed to be as low as possible without recessing the whole thing into the deck and it should have as small of a footprint as possile. Also, because a compass won't be needed for 95% of the paddling that he is going to do, it should be removable. I decided to use a removable Skipper (Aquameter) but unfortunately the mounting base for this particular model sits almost an inch high and has a really lousy release tab that is a bear to operate. I discarded the base and fashioned a bayonet style latch from the existing housing. This secures to a stainless steel rod threaded through a fiberglass "CUP" built to the same radius as the mounting base that came with the compass. The "CUP" is recessed into the deck about one inch.
The plug that I cut from the deck can be returned to it's original position when the compass isn't being used - effectively eliminating the unsightly hole that would otherwise be there. This was quite a bit of work to gain one lousy inch of clearance but it was fun nonetheless.
Joe