A 340 Tach question....

I put a clock in the center position of my rallye panel. The factory supplied it's power directly from the hot post of the amp gauge. I choose to add a inline fuse dropped down near the column cover and wrote CLOCK on it with a Sharpie. Funny thing though, I always set the neg. battery cable off when I park the car so that clock never shows the correct time. DOH
Anyway... I think if I added a tach I would place a tiny toggle switch down there somewhere to turn the thing off and on as needed. Might double the life of the tach.