you ever given any thought to manufacturing FE valve-cover spacers?.......... Just searched and noted Branda sells 1-3/16" tall ones for $190. I'd think a 1/2" model and 1" may have a decent market.
Just figure whipping them out on your CNC would be fast, fairly economical and leave you with a bunch of cut-outs. Cast aluminum valve cover spacers for the big block Ford engines. Blanchard ground finish matches our cast aluminum valve covers perfectly. Fits all Ford big block 390-427-428 engines. Price per pair.