Didn't I see that the older Jeep 50 pounders are 6 volt?
Probably the same manufacturer as you have already tried, but thought I'd share what little knowledge I have.
My grandfather served in the China/Burma/India theater and was flown out of China on one of those "between the mountains" flights.
There were hundreds of them, but what are the chances..........
I owe your uncle and his comrades a lifetime of thanks!
But it goes to the life history of the car. If we found service records for the third set of tires @ $12 per tire we would be downright giddy over having them.
Kudos to the OP!!
A top quality 00 cable can be had from Battery Cables USA.
They will create one to your specs and the proprietor is a terrific guy.
https://www.batterycablesusa.com/battery-cables.html
Just be mindful of the other crud that may come loose.
I flushed the radiator on my '39 Buick with vinegar, then the soap from a dishwasher gel pack (they are all super-low sudsing).
Anyway - busted loose all kinds of crud in the block - that subsequently clogged my radiator!
The old stocking...
There is a '39 pickup making the rounds on Barnfinds.
https://barnfinds.com/80-year-old-clean-slate-1939-ford-pickup/
The Ebay listing shows an interesting speedometer face with shift points indicated on it.
This is different from the speedo on my '39. What do you guys know?
The inner and outer components can be a little tricky. The sticky points should be showing themselves as scuff marks on the plastic.
I think a little sandpaper on the spots that are binding will do the trick