RE: Scratch built tow cables?
For the cable itself,try going to Lowes or Home Depot and find the section that has hardware for hanging pictures and mirrors.
"Braided Wire,Mirror Cord made by Hillman"
For the loops? Good question,havent figured out how to homemake nice ones myself.....need very small swage kit.
I tried using heat shrink tubing,but it doesnt look right.