If you solve the mystery, let me know. A friend in OR and I have never found the answer. I did find a bulletin that described trimming the cable to resolve a problem when used with the electric wiper motor but I can not find the definitive answer. I suspect that there was either a different switch plate or a modified mount to give it the ability to hook up to both cables yet let each one work independently of each other. just e-mailed some info to the address in your public profile. Hope it helps.
Last edited by Greg_H; 04/10/2017 3:07 AM. Reason: additional comment
