there seems to some question and confusion, about 12 volt VS. 24 volt radios in shermans. perhaps a gallery of schematics will help answer the question.
from the volume 8 SNL
at some point the color coded system was dropped and a number system, was instituted, along with this change, the brake lights were deleted. (at least on the A3 shermans). unfortunately the 1954 manual does not include a wire schedule. and I don't believe anyone has ever found a universal schedule to explain all the numbers. of course when the early tanks were rebuilt, they tried to put the new system into the old conduit runs, which of course created more anomalies. and more confusion.
most armored vehicles used woven brass flex conduit with a "garden hose" fitting soldered on the end. the electrical connection was usually a bakelight connector with very small set screws for the wire. and a slide fitting over the set screw section.
- TM 9-759 1943, 1944, 1953
- TM TM 11-2748, 45. Installation of Radio and Interphone Equipment in Medium Tank M4A3 or M4A3E2, 75-mm Gun, Wet Stowage; Medium Tank M4A1, M4A2, and M4A3, 105-mm Howitzer, 40 pages. PB 80907 - BSIR 7(1):34; 10/03/47