Attached is a generic drawing of how a late '50s and early '60s GM turn signal switch works. Wiring colors are correct for my '57 GMC. Ignore the colors for anything else. The top drawing is with the turn signals off. The center is signaling a right turn. The bottom is signaling a left turn.
'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.
