I don't think there is a 3/8- 14 tread on any Stovebolts. Or that size was ever produced for anything.
It is probably a 1/2-13 thread.
When I mounted a 235 on the engine stand, I used 1/2-13 bolts.
In fact, that is the only size bolt I have used, be it GM, Ford, or Chrysler.

No DB, there are no stupid questions on this site.
If it saves someone some hurt or money, we are here to help!

Don


1967 GMC 9500 Fire Ladder Truck
"The Flag Pole"
In the Stovebolt Gallery
1946 2-Ton grain truck
1946 3/4-ton pickup,
1953 1-ton pickup
1957 1-ton flatbed dually,
1954 Pontiac Straight Eight
Of all the things I've lost in my life, I miss my mind the most!