This looks to be an interesting hobby - I do hope you have invested in a good kidney belt.
I had a 1960 IH half ton once - the Parts Mfg list that was in the glove box was of major interest, and a hoot. They obviously were building the things from a parts list that was altered regularly depending on best price and availability.
From a racing stand point, that could be good. It means the cars are designed to be readily adaptable to anything that comes from a third party vendor.
In response to your PM, I know little about this type of racing but would be happy to consult in areas where I have dabbled.
My first thought (other than the kidney belt) is that having your own welding setup (both gas and arc) will be a must for keeping the little beasty on the track...

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