The image below shows the switch (26) on the schematic.
Red wire (#30 at connection #12) goes to the fuse box (Fuse 11), the main light switch, and battery positive. This should be a thick wire.
White wire (#34) appears to go to the adjacent signal switch in the column.
Red/White wire (#35 at connection 13) also goes to the light switch.
Black wire (#15 at connection 8) goes to fuse box (Fuse 8) and to the rear relay board in the large connector at pin 8.
Yellow wire (#36 at connection 10) also goes to the rear relay board in the large connector at pin 1.
Doesn't look like you can do without any of these. Haynes has a good manual for the 914 with all the schematics. May prove helpful.
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