I had to re-use the gaskets on my 350 a while back. It worked, but I'm not sure if it was the right thing to do or not. I had a bad leak, so I was going to replace my gaskets, but when I got it on, I realized that they wouldn't fit my intake, so I had to use what was aleady there. I just dabbed on a little rubber gasket stuff(not sure what it was called) in a few places[around the bolts]. Like I said, I don't know if it was right, but that's what we did to get by until we got another gasket.