Do I need sealant/"gasket dressing" to replace the valve cover gasket on my 1975 Chevy Cheyenne?

It's a 350-V8 light duty (c10) truck. Need to know before I go pick up a Chilton's/Hayne's manual. Would be convenient to know beforehand so I don't have to purchase the book, then flip through it and return if I need it. I already have the gasket.