The red is for the oil light. I was going to tee off of the oil sender so I could run an oil pressure light along with the oil pressure gauge (sometimes a light will grab your attention faster). I didn't get around to doing it though. The amber is for the parking/warning brake light (I didn't get this working yet though lol). Everything else works like a champ though. I've had these in about 2 years with no problems. I will get around to finalizing the red and amber when my 67 Barracuda is done.
The smaller gauges are 2" (or 2 1/16"?), the speedo and tach are 3 3/8".
DartGTDan I sent you a PM with his email address, I don't want to post his email in a public forum until I get his permission. I sent him an email asking.
Here is an old thread at a different site discussing his gauge panels