I went to a salvage yard and looked for early to mid 1980s Toyota Tercel 4x4 Wagons. These vehicles often have a clinometer gauge set very similar to the Toyota trucks. I pulled out the first guage I could find because I planned on painting the cover with some black trim paint from Walmart. The Tercel dash has much more slope than the truck/4Runner dash, and to make the clinometer fit properly to look "factory" the gauge cover must be trimmed. The gauge cover has a bit of excess material along the bottom edge that allowed enough leeway to trim it to the correct angle (almost). The trimming I did was not quite enough to get the front/rear gauge to show "level" while sitting on the dash as I wanted it to. The front/rear tilt indicator was showing the truck as going down a steep hill even though it was level and I turned the adjustment knob as far as I could. I took the gauge apart and literally spun the front/rear tilt picture in the proper direction on its axis to bring it to level. After a few tries, I put the gauge back together and got it in the right range. Then I wired it up to the dash lights and dimmer switch. Note that wiring will vary with different years, so I will not know what wires you will need splice in with. I didn't record what ones I used on my '85 either, but I simply followed a wiring diagram in my Hayne's manual.
Those of you who have actually seen the genuine truck version of this gauge will notice the altimeter is missing. In its place is a 4WD indicator light similar to those found in a 4x4 Chevy. I wired this into the original 4WD indicator light in the dash. No it's not a useful gauge, but it looks kinda neat and can easily be replaced with something more functional.
The first gauge set I bought cost me only $10. Unfortunately, since I bought the first one someone else got the same idea here and stripped most of the remaining clinometers from the local yards. I got two more but I didn't get quite the deal, and I've seen the Tercel gauges selling on Ebay for some good coin. Plus, price always depends on which person I talk to at the yard (they make up prices on the fly). It is still very cheap compared to the "correct" one from a truck. If you cannot find a used one, a new one from Toyota costs around $250. Yikes, that is a lot of money for a couple of simple gauges. The nice thing is, the excess trim around the bottom of the cover will allow this gauge to be installed in any vehicle. You just have to trim it to fit the dash contour. My 1990 4Runner will get one next.