A home made trouble shooting tool I have consists of an old -30 0 30+ underdash ammeter with a 4 foot set of #12 wires attached. Each wire is terminated with an alligator clip. One wire has a 40 amp inline fuse near the meter. Most modern volt/amp/ohm meters have an internal 10 amp fuse. Anything more breaks the modern meter.
My tool allows you to unhook one end of the wire of the circuit to be tested, attach the tool between the wire end and where it had be connected and activate the circuit to see current draw. It doesn't really make any difference which way you hook up the tool, the meter will read + one way and - the other. If current exceeds 40 amps the fuse blows, but is easy to replace.
I probably use this thing twice a year.
Where are you in Texas?
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
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