I ended up just getting the replacement manifold. Summit Racing had the best price. The unit was a Dorman, and both I and my mechanic were impressed by the quality; the machining was right up to OWM standards.
I bought the mounting bolts from the local Ford dealer, as I wanted to make 100% certain that those were right.
Also ended up replacing the up-pipe - when we removed the manifold, the up-pipe just fell out of the upper flange... the gasket was just gone. I would have preferred to do the bellowed up-pipe, but I wasn't about to tear apart half of the engine bay, right now. The factory unit went in with no additional disassembly. I also didn't want to wait to have one delivered, and the factory up-pipe was available at the dealer.
We ended up having to torch off the heads of all eight manifold bolts, and the two bolts that connect the manifold to the up-pipe. Then heated them red and sprayed them with penetrating oil. Came back in an hour and they actually came out smoothly with the extractor.
I installed the RiffRaff FRx that's been sitting on my shelf, and my own bypass oil filtration kit (similar to the "SpringerPop
" design, but mounted differently) while he was working on the exhaust, so it was a pretty productive day. I like being on good terms with my mechanic, so I can use his shop and tools - fighting the fuel test plugs out of the heads with visegrips and such was going to be crazy, but if you actually have a 5/16" square socket, they come out with no more trouble than any other bolt.