[IlludiumQ36]

Doubling back the wire is certainly a viable solution. Using resistors of known values allows me to trim the results as I'd see fit. I've already decided that I'd parallel two of those resistors... that would be 100W. I don't think it was really needed but I did not want too much current running through the gauge.

This gauge really is for charging/discharging the battery, not to measure the total load on the system. In the charging direction, all the current through this pair would be feeding the battery. Discharging kind of assumes no or poor alternator/voltage regulator or motor not running. To the rest of world, were everything be operating properly (regulator output voltage higher than the battery voltage), would be from regulator to the splice & out.

30A through would ask the 2 parallel resistors to dissipate ~25W (P=I*I*R), @ 60A -> 90W. I doubt my alternator can produce that anyway. I know that the 12AWG wire should not be carrying much that either. Plus, the fusible link would be less than that.

As for the fuse, I tend to agree. I really did not think through the case where my 12AWG separates, I blow the fuse & then nothing works to the battery. That said, I still don't like the idea of running that much current through that 50 year old magnet wire & the gauge internal connections. Good chance that it becomes the fuse instead. Maybe you've influenced me to go to 2A. I like my gauge.