Brendan, I don't have an earlier diagram. If your wiring is already a rat's nest it might be a good time to go ahead with the new harness.

I'm in the process right now with my '56. I'm using a Hot Rod Wires harness. If you want to stay closer to stock check with the specialty vendors.

"It's just a phase. He'll grow out of it." Mama, 1964

1956 Chevy 1/2-ton 3100
1953 Chevy 6100 "The Yard dog"
1954 GMC Suburban Now with a new proud owner.