Case - I'd suggest posting this on the 1948 - 1960 page too. That seems to get a lot more traffic than the pre-48 page does. And the 5 lug x 8" circle was used well up into the 70s by IH, Studebaker, GM, Dodge as well as Ford. So you might watch sites aimed at those makes. A good one is
www.oldihc.org. Another is
www.yesterdaystrucks.com. I'll keep my ears open, but at the moment don't have a line on any. What I've done is avoid driving the Interstates and take backroads when ever I go somewhere. I stop at all the old tire shops I find. Good luck. Stu