Has anybody done this before and if so, what were the problems and results. I was thinking rather than the clock, I could make an adapter to go in and hold the gauge back about how the second photo shows.
I like the idea and have been thinking of this also. either where the clock should be or that little rectangular area outside the dash display, where the rear defog or cruise switch might go? I am 1968. It certainly looks doable either way. I think using the blank clock face and adding the gauge info would be slick. I don't want it to stick out like a sore thumb...
I don't want it to stick out like a sore thumb... Boy howdy! That is the trick. I can get a 1-1/2" 100psi oil pressure gauge and since I own a machine shop, I can build whatever is needed to make a mount to hold it there. It would basically be a flat sheet of metal match painted to the rest of the background with the gauge fastened to that. I can get a black face, white letters, red needle which matches the theme of the other gauges. I'm gonna give it a shot. Worst case is I'm out $60 for a gauge I don't use. I am a little concerned about having a mechanical pressure gauge, but the 1-1/2" all all mechanical. I'll keep looking.
I am doing just what you suggested only with a tach. I took the little plastic square that blocks off that opening and installed a mini tach. Haven’t installed the dash yet but getting close.
I found this also: https://www.intellitronix.com/create-a-dash-gauge-kit This has lots of possibilities as it looks like the digital faces are pretty flat, and they include a sheet of black transparent stuff to cover. Kind of spendy though. Plus I don't need or want another speedo.
