What did you do with the carb and air cleaner hoses when you installed the valve covers without those ports? I'd like to dress up my 318 some but I'm no mechanic. Learning as i go.
Have you consider cleaning up what you have? When I got my 73 Charger I took the after market ones off, I thought they looked awful. I found a set of original valve covers off a 74 car, I think I paid like 20 bucks for them. After a good cleaning in the cabinet and a trip to the sandblaster I primed and painted them mopar blue. They look great! Much better than some after market ones. But if you want after market there are many out there. I already sold the ones I had on my car. You should find many options, just make sure they have the knock outs in the areas you need to hook things up. You'll need new grommets most likely. Should be good to go after that.
