Nice work. I was thinking the same thing this am for out trucking around on big bodies of water. In the winter I use my old garmin etrex legend b&w GPS. It does a good job of getting me to my pre-marked way point and leaving a trail mark to follow, but it does not have lake map software.
My thoughts was to add a ram mount ball to the inside of my pickup so I could use my 997HB with my map chips out ice fishing. Would need to pick up another puck like you have and test places to mount. Would be nice to set puck on dash and get signal, but could fabricate a suction cup mount.
This would also be awesome as I wouldn’t have to manually type way points from my summer fishing into my old garmin unit.
Anyone do this? Nice work on your kit.