I had to redo my gasket, I take the blame for not letting the gasket adhesive set up long enough before I installed the cover first time, the gasket "oozed" toward the inside around the rear most head bolt on the driver side. This time I used a center punch and punched
marks around the edge of the valve cover and the cylinder head where the gasket seals, hoping this will help "grip" the gasket, I used the same gasket adhesive, Permatex yellow, applied it to the head and put gasket on, let it set up for a couple of hours, applied sealer to the top of gasket and installed cover and let it set for a couple of hours before starting engine, have put about fifty miles on it, have checked the cover bolts twice, have tightened about 1/2 turn more each time, no leaks so far. i t is really a bad design with such a long area and those notches around the head bolts and only two cover bolts. Just my opinion, others may vary.
Eddie