Black rallye gauge

Sunpro CP8215 has a couple of black plastic spacers in it. They'll hold it close enough to correct height. Most ppl just lay the volts screen on top of the original alternator screen. If you think the raw edge of the volts screen will show, hit it with a black sharpie.
The part of white needle on the bottom of the volts gauge is both counter balance and stop. The cast metal post in the center of the housing pod will need clearance cut for that part of the needle.