Upgrading to Dakota Digital Gauges
Over the course of about 3 weeks, I upgraded Silverback from stock gauges to Dakota Digital Digital Series III digital gauges. There were cheaper solutions on the market, but DD had the best features and capabilities in my opinion. They offer a number of add ons such as ambient temp, gear position, fan controllers, etc. All of which I'm using. They even have some other pretty interesting things like GPS speed etc which I'm not.
Silverback had a number of wiring issues when I started this upgrade. The previous owner did a wiring harness swap out to a Painless Harness. However, the installation left a lot to be desired and many things were either not hooked up (eg interior lights) or hooked up wrong. The fuel gauge was wired wrong, the interior lighting was missing, gauge wiring was a mess especially in the center console area. So after a significant amount of disassembly to get to the dash wiring, I had to chase a lot of this down. Luckily, I'm an electrical engineer so it was more time consuming that difficult.
Removing the old main gauge console with speedo and tach was the most difficult. It requires dashpad detachment (not removal), dropping the steering column, and disconnecting the vent lines from the HVAC, and disconnecting the headlight switch (this was one of the trickiest things).
As you can see from the fully disassembled pictures this is not for the faint of heart. I STRONGLY encourage anyone doing this to use a label maker and label EVERY wire as you take it off things. This will save you a lot of pain later.
There are several new sensors you have to install which are pretty straightforward including water temp, oil pressure, tach, speedo at the tranny. Also I added new sensors including ambient temp and gear position (this is missing in a 71 so a nice add). Later after this initial upgrade, I changed my electric fan controllers to the DD controller which is nice because it's driven off the water temp on the new gauge. Most of this is pretty simply just wire routing, then configuration. Gear selector install took some creativity since it's basically a rheostat that they read the voltage off of based on the position its in so you have to tell it what each position relates to. Also, you have to fabricate the mount but they give you most everything you need to do that with basic tools and a grinder.
Once it's all installed then you have to do some calibration on the road for speedo, compass, etc. Again, very simple but it does help to have someone with you since you'll want to calibrate it with the GPS speed on your phone and not too safe to do both by yourself and drive.
I think it turned out well and I'm very happy with the upgrade and extra features.You can see the before in the first pic and the after at the end.