I think he is talking about the other gasket at the head.Looks like the glob of worms I pulled out of one of my customers ponds today. Never heard of those gaskets. I had the same problem with the long tubes on my 70' Olds until I bought these one collector gaskets at Super Shops. Member those? Can't remember what the hell brand they were though.
I have another suggestion though. Cut that B.S. off of there and weld on a V band. 20 bucks with a clamp.