Before I would cut up a dash and screw on a plate, I would just add hang down gages. Temp, volt, gas. Not as "risky", damaging or "custom". Like I said it's a one time thing. You are not wiring on your head, just putting in a few fasteners. With a mirror if you need to, as said. You can buy "Quick Acting nuts or knobs. They are threaded normally, then have a plain hole drilled at an angle. Tilt, slide on, tilt back straight, thread on and tighten. Faster and easier than wing nut. Don't have to "start" the threads blind. Not sure if size you need is available. I have used these, they work great.
http://www.carrlane.com/catalog/ind...0B1713050245221E0107070F1A3C3B285352415B
