I decided to spruce up the engine bay, since I was digging into the intake manifold anyway. So I ordered a set of Ford Racing polished aluminum valve covers (M-6582-E302P). I got them on eBay from a drop shipper for $127, and will be replacing a set of thin stamped steel covers that are prone to leaking. These new ones have a 3/8" flange to help keep leaks at bay, (screw-in) baffles, and are 3.75" tall to clear most roller rockers.
The polish job was pretty good, but required some more hand polishing around the bolt areas. I also had to thoroughly soak the insides down with a solvent to clean out the grime and aluminum shavings (!) from the manufacturing and polishing processes.
I also bought longer stainless bolts than I used previously. I bought 1" bolts at the local Lowe's, but cut them down with a Dremel to 7/8" for a perfect fit.
Lastly, I went with a Ford valve cover gasket set (M6584A50) bought on Amazon. These things have a steel core and a rubber bead all the way around the perimeter for a good seal. Apparently they can be re-used too if needed.
Mentioned in this post: