1949 3600 with 235 and SM420. Converted to 12V and retained the stomp starter.
OK thanks guys. Didn’t imagine that the factory harness would come with splices (or even stranger, splices with different gauges!). So I’ll go searching for splices downstream of the negative terminal.
Just to clarify (‘cause wiring is not my expertise): the two wires on the right (positive) terminal are for power out to charge the battery (10ga) and power out to the fuse block (16ga). On the left (negative) terminal is a single 10ga wire that splices to 10ga coming from the voltage regulator B terminal, and also splices to a 10ga wire powering the ignition switch.
Somewhere on that 10ga wire from the left (negative) terminal there should also be splices for the heater (12ga), brake lights (16ga) and turn signals (16ga). The wiring diagram makes it look like those last three come directly off the left (negative) terminal, but that’s obviously incorrect as I only have the one 10ga wire connected there (and the turn signals, fan and brake lights all work)