Less than that. Voltmeters draw a fraction of an amp. "the better the meter" the less they draw Something like 1/8---1/4A fuse would be oodles. I'd just put in whatever you can find locally that will protect the wiring. 1A, etc
Thank you, I'll try a 1amp fuse this time. Ordered another gauge, but trying to figure out how I'm killing them. Would a weak ground kill a volt gauge? I used the same nut that a little ground strap connects to under the steering column. I thought these volt gauges were pretty simple and foolproof?