I believe I mentioned that with the E38 ECM I needed an electronic speedo. That's not a big deal and then I tested my Tach and that didn't work either. So, rather than try and find originals that work, or plop down for reproductions, I decided to stick with my method of burying Autometer gauges inside the stock housing. The fuel wasn't too bad as the scale stayed the same, however both the tach and the speedo scale are completely different on the new gauges. So, I used Adobe Illustrator to design these new faces after scanning in the old ones.
They should fit in the 4" bezel and also work with the smaller needle of he 3 5/8 gauge. I think using the smaller needle will keep it looking closer to original. Plus the smaller gauges were considerably cheaper than the big boys.
After that I laser cut them out on my Universal Laser X2 660 CO2 cutter. Turned out really nice. Product I'm using is Rowmark Lasermax microsufaced plastic.
Next step is to get the original gauge face cut to accept the new digital display and the trip reset button. Then bolt it all together!