You all probably are sick of this thread but I thought you might like to know how the project came out.
Upon closer inspection of the after-market air cleaner, I found an unused 5/8" hose nipple - pretty obvious but I still missed it the first time around. I got two new PCV grommets at the local Chevy dealer. The grommets have a 3/4" hole - course the valve goes in the driver side. For the passenger side, the local AutoZone has a plastic elbow ("Help" brand mentioned by Mike Romain) that is 3/4" on one end and 5/8" on the other - it's even a 45-degree bend which should fit better than a 90 would. It's listed as a Ford part. A piece of 5/8" hose to connect to the air cleaner and I'm in business for under $20, including new valve, hose, and non-vented oil cap. Pretty simple, but all your posts really helped me understand how the system is supposed to work and what I needed to do to fix it.
Now I just need to finish stripping the paint off the covers, which is why I took them off in the first place. Yes, somebody actually painted nice cast aluminum valve covers - a coat of primer and a coat of enamel. At least I don't have to take the blame for that one! Here's a tip - some stuff called Aircraft Remover made by Klean Strip (disclaimer - it probably causes cancer, impotence, and bad breath). I found it at Bumper-to-Bumper. Not cheap - $9 for an 18-oz spray can. But it works way better than the Bix I tried first - although it still takes a couple of coats and scrubbing with steel wool. The fins on the covers are polished and I'll buff them up with progressively finer sandpaper, ending with 1500-grit. By the time I'm done, I'll have $30 - $40 (and a whole lot of work) in them - about what a pair of chromed steel covers would cost but I think these are way cooler.
OK, bring on the wisecracks about Ford parts on a Chevy engine in a Plymouth coupe - guess that's street rodding!