wasn't the 53 still the cloth covered wiring? maybe yours has already been replaced, just poorly - looks pretty good compared to most 60 year old trucks, just need to solder and heat shrink cover the patches properly
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics