4 way flasher info

I need help with this one. My 66 sport fury is equipped with 4 way flashers which appears to be OEM. During disassembly it wasn’t properly documented and as a result I never reinstalled it. It does not show on any schematics in the FSM so I was wondering if someone has something they can share on this. I need to now the wire placement and whether or not it requires a second flasher. The bulk heads just spliced into the existing turn signal switch.
Thanks.

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4 way flasher info
Author: rkrochen