bowtie65:

You might move you post to the Swap Meet area and post under Truck Parts Wanted. By doing so, you will get more replies. In the interim, try these sites for the '65 Chevy truck underdash harness:

www.chevyduty.com (Riverside, MO)
www.lmctruck.com (Lenexa, KS)
www.oldchevytrucks.com (Independence, MO)
www.bowtiebits.com (Wichita, KS)

I hope this information is helpful and good luck with your '65.