I saw several cammers at the SAAC national convention when it was here several years ago, don't remember what year it was. There was one that was converted from an original cam-in-block engine that had an exposed toothed belt cam drive.
I just did a search on SAAC and found out the national convention SAAC-29 was here in Southeast Michigan last June and I missed it. The SAAC national convention has to be the largest collection of Shelby's and Cobras and other vintage Ford racecars held each year.