If you could use coarse thread these may work:
http://www.mcmaster.com/#catalog/115/3172/=28zbp1

I've used some of the #6 and #8 styles, there nice heavy steel or malleable iron ones. All of the styles 6-12 should be nice.
I'd stay away from the zinc or pressed steel ones.

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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