You ever tried using AC sealing washers before? I used them on my truck as I had a problem with copper and nylon gaskets not sealing good on my emission era truck. Guy at work told me he changed all his out for those sealing washers for A/Cs that has the raised rubber center on a metal washer to prevent over crushing. I actually like them as I have been able to get a good 4 oil changes before I have to start consider changing them.
My 56 is a rare case as I never replaced mine and it is over 30 years old and doesnt leak so I wont be touching that gasket till it starts leaking.
Btw how much are you paying for that Lucas Hotrod 10w30 oil? I pick up a case of 6 quarts of VR1 10w30 for $30. Ive done my oil change 4 times, next oil change and I got a whole oil change without having to buy another case of the stuff.
1956 Ford Fairlane Town Sedan - 292 Y8 - Ford-O-Matic - 155,000 mi