Unfortunately, both the Ads programs have their own search routines and they don't honor any of the special suggestions I was making.
Using the "Advanced Search", I put in "Case RC", then specified "All Terms" under "Ads Much Match" (that "much" is a typo, I'll fix that), then putting "Tractors" for the Category to search. This brought up the RC that is in there but also brought up 6 other Cases. It was close and didn't have too many misfires.
I also just tried the google method with "site:tractorshed.com case rc photoads -archived" and that returned some useless links, but included the Case RCs. There appears to be only one in there now.