Best sealing valve cover gaskets

So....I ended up working on the cast aluminum ones I bought, i.e. new grommets and some wrinkle paint, also added the oil fill hole, I did notice the flange on these Holleys have a raised ridge around the center of the flange and the blue Moroso gaskets I bought said use only on a flat flange.ARG! So I changed gears and bought some Real gaskets (orange silicone but only 1/8" thick) and straightened my steel units, reinstalled and torqued in inch pounds.....they still leaked ARG! again. I thought, what the HELL this is supposed to be an easy job....So yesterday for ***** and giggles I bought some Felpro hard composite POS gaskets to install with the cast covers (no one stocked the cork ones)...Well yes they leak like Holy HELL and I mean leak, they look good but thats about it. Tomorrows is yet another day.