Tachometer is an Autometer Pro-Comp 3 3/8" electronic gauge (p/n 5161). I don't like the look of tachometers outside the gauge cluster, so I spent some time making it fit into the 510 gauge cluster, and I think it came out ok! Note I re-used the "visor" that fills in the gap between the gauge and the front portion of the dash. If I would have painted the silver edge of the gauge black it would probably look even better.