Sorry should have specified, look for a vacuum coming from the breather. If everything is good without the hose connected there should be a slight pressure from the breather, if the gasket is blown there will be a vacuum coming from the breather.

 

I will check that tonight. Good info!

Are there any air cleaners to stay away from? I have heard that rechargeable/oiled filters have caused expensive damage to mass air flow sensors in newer GMs. Matter of fact, I have heard they even void your warranty.
Obviously and older vehicle and no warranty to worry about here... just askin.

 

Our engines use MAP sensors so the oil does not affect them. That said I do not like k&n filters because plenty of tests have shown the filter poorly compared to paper.
I'm using a standard 14" round paper air cleaner.