Current meter shunts

[Chuck]

If you are going to be pulling upwards of 50 amps from the supply,
consider using commercial meter shunts. www.mpja.com sells surplus
shunts in various ratings at $7 & $8 with a 100 amp unit available with
100mv output. With a cheap digital panel meter (also $8 from mpja), you
could have a direct reading meter resolving to one amp. Best of all,
essentially no voltage drop to be concerned with.

Chuck