Search 60-66 3/4 spare or 60-66 3600 spare or 60-66 c20 spare and all those using individual years I.E. 1960 3/4 spare then 1961, etc.
This one is sold, click on "see original listing" and scroll down if you want to read that it says "3/4 Ton 8 lug bolt". It is listed as 55-66. Found this under "completed listings". I was not searching to buy just searching for you to be sure there are two types.
http://www.ebay.com/itm/55-66-Chevr...53289631?hash=item19ff0dfe9f&vxp=mtr

Another sold one:
http://www.ebay.com/itm/55-66-Chevr...81671214?hash=item3cf95d2e2e&vxp=mtr

Just keep checking. They seem to all sell.
You really do need to put a wanted in Stovebolt. That's what it's for.

AS HAS BEEN MENTIONED: It would be fairly easy to modify your plate, make a new plate or fab an adaptor plate. Wheel studs are cheap and very, very easy to install. Maybe you have enough room on the plate to locate that third stud after removing the misaligned one. No one will see the mod behind the tire.
http://www.oreillyauto.com/site/c/s...t&model=C10+Panel+RWD&vi=1442230



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