There have been several others who've installed a set of weather instruments and there are several different approaches show in the thread "A few mods in our new to us 17B".
I've always had a barometer etc. on boats and got in the habit of giving it a tap in the morning to see how my day was going to go. So, inspired by the other posts and the set at Lee Valley being so reasonable I made up a base plate for them.
I wanted to mount them to drywall machine screws so I needed a keyhole slot. I didn't have a bit for that so I improvised. 1/2" milling bit straight in, 1/4" bit sideways and a 1/2" Tee slot cutter in and sideways. More fun than going to Busy Bee and buying a cutter for 8 bucks.
I wasn't going to buy two expensive bits just for this project. So I used a hole saw and then a 1" milling cutter to remove the excess wood. Could have used a chisel but I'm lazy.
Went to slap on a coat or two of polyurethane and found the contents had turned into a white hockey puck.
I looked at other clear finishes I had on hand; some varnish from Turkey when I keep my boat there, great stuff but thick and slow drying and not suited to this job; also the oil base Varethane; the Deks Olje is great stuff, beautiful appearance and easy to sand but put on # 1 flat and wait 3 days before putting on #2 gloss. I'm not that patient. Quick trip to store and a new can of water based polyurethane. Looking at the other products made me appreciate how good and easy to use the water based finishes are.
I like the location where I placed it. I can take a quick peak in from the door and see and it's very visible in the trailer. 80 degrees in there now but only 50% humidity so it's not quite as bad as some other places.
So I'm back to my old routine, get up and give the barometer a tap-tap.