My 1965 IH504 gas is negative ground. Hope this helps as I think 1965 was the first year they produced them so yours should be the same.
Also, could you please give me the dimensions of the drawbar under the tractor: How long, how thick, how wide, and how thick is the pin at the end that connects it to the tractor? It is very important for me as I have posted the following message on this board:
I've tried a number of boneyards on this site as well as the classifieds here. No luck yet.
It should be around 45 inches with a slight curve to go under the differential. The swinging front pin looks to be almost 2 inches thick.
I think it might be the same as the drawbar on the 544 and the 560 Internationals.
Is this the same drawbar as on the 504, 560, 544 Farmalls?
Thanks in advance.