You can glue the gasket to the valve cover with weatherstrip adhesive and leave the lower surface of the cork/rubber clean so it won't stick to the head in case you need to pull cover off later. I don't normally use sealant on the head side of the gasket anyway. I wipe it with new engine oil and put it on and tighten the cover screws. That oil will soak into the cork and make it swell, making for an excellent seal.
BTW, you should be able to run a 235 at 450 RPM until the engine is warmed up without the valve cover on without leaking any oil.
Carl

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission