Pats58:
They did make script valve covers for the later heads too, not just the offset. They will work just fine if the offset hole thing isn't a big deal to you. Most people wouldn't notice or know the difference.
The older engines have a tube that runs down the rear of the engine on the right side. It is called a draft tube. It is ventalation for the crankcase. On the intake manifold with the filler tube, the filler tube is also a vent for the crankcase. If you replace the valve covers with no vents, you'll want the manifold you are seeking in place because you will be eliminating the vents on the valve covers.
Your original question was about the stock air cleaner fitting. That will be determined more by the carb you have in place now.
I will be assuming that you are thinking of getting an original oil bath air cleaner, and you do not have one laying around. If that is the case, take your current air cleaner off and measure the diameter of the top of the carb where it attaches to the air cleaner. Take note of the depth of that flange. The original oil bath air cleaner will be tightened on that flange with a hose clamp type mechanism. It is not attached from the top with a wingnut and a stud in the center of the carb. The oil bath air cleaner has a wingnut in the center of its top, but that is to service the air cleaner, not to secure it to the carb.
If your carb is a later model, it might not work. Can you tell us what carb you have now?
If you want, I'm sure I have all the parts you need to bring it back to a stock look.
