70 up charging system upgrade question

Del I only got to test batt -ve to "batt" on switch with everything hooked up.
Results are in quotes below.
Once I thought I found drop in red wire, I started tracing both it and the big black wires back to splices. I stopped there. Good news is I haven't cut/changed anything. I can tape/protect to run more tests. Sucks I'm doing this outside as it limits time.
Thanks Del, it's much appreciated.
Results in quotes
4spdragtop said
Birthday shopping for 4yr old granddaughter Lennon done, lol.
Hooked everything back up, rigged a lead to batt -ve and to "batt" on back of switch.
Key "on" 11.18 V
Key "start " 10.2 v
Battery static is 12.20 V.
Ampmeter bypassed(MAD)
Thanks Del. More tests coming.
Click to expand...

67Dart273 said
Well you may be off track. What are the two voltages reading with key in run compared........blue "run" and the red coming INTO the switch? That will tell you if the drop is in the switch/ or connector, or whether the drop is upstream in the red? I'm missing that somehow. If those splices are "solid" whether they look bad or not may not be the trouble.

How does the "big red" (battery feed) get through the bulkhead? Is it still "the connector" or drilled through and wire straight through?
Click to expand...