For a GPS I use a Garmin C550. It has the brightest display I have seen and a real sensitive receiver. It also has nice logic and is small enough to work nicely in Amphicars or whatever car you put it in. It speaks road directions, if you want. It has internal batteries that run for hours. Normally you would then you can just plug it into your cars cigarette outlet but don't you dare do it in your positive ground Amphicar. That's just one reason I converted my cars to negative ground. They're currently on sale on costco.com for $199.
For a depth sounder I use a little electronic thing called the Hawkeye that cost only about $60 and works perfectly. I have to make up or modify the mounts to work to make it fit nicely in the Amphicar but it's a great gizmo. You can see the dash mounted part fits nicely alongside the heater controls and the sounder part tucks under the front bumper bracket. The wire goes through a drilled bumper mounting bolt (Thanks to John Bevins for that tip) and the whole installation is just about invisible. It updates very quickly, works up to 100 foot depth, has resolution down to tenths of feet, and has internal logic that is just perfect for Amphicar use. It turns on with the push of a button and turns off when it's out of water for a few minutes or you turn off the ignition. I don't remember the brand right now but if someone wants the brand or model number let me know and I'll dig through the paperwork to find it. I have one in each of my Amphicars.
One of the photos that shows the sounder also shows my latest find. I'd been looking for years for a lift that would work with Amphicars but was light enough to not be a permanent fixture on my garage floor. I found this one at a local car show and the guy who makes them lives in my town. He's been selling them for a couple of years now and they're absolutely perfect for Amphicar maintainance. Big hard rubber pads that lift right on the frame rails and the car is very solid and stable when lifted. The whole thing weighs only about 150 lb. and has spring loaded casters on it so it can easily be rolled around. It also comes apart with 8 bolts and the parts can be easily carried by mortal humans, stored upright against a wall or stowed in a vehicle for transport. You use a power drill to raise and lower it and it's screw jack design makes it "lock" at any point along the way. It's made in the states so it's not exactly cheap at $1995 but they're on sale for $1795 until Father's day. Let me know if you guys are interested in this lift and I'll post more photos of it. It's a really great find.
Actually, the ladder is at more of an angle that it appears to be in the photo. I'm always somewhat concerned about those earthquakes but I've lived here for 30 years any only felt a couple of minor quakes. Actually, the first and strongest quake I was ever in was in Southern Illinois. Strange, especially because at the time I had no idea that quakes happened in Illinois.
It looks like the Lake of the Ozarks meet is going to happen again. Complete with the big race boats. I'm planning on being there. I hope you, and lots of others, can show up. It was a great time last year.