Finally got my stupid valve cover to stop leaking. Or at least it seems. I took everything off again the other day and cleaned the hell out of everything. I wiped and wiped the head with mineral spirits, then i sanded it, then i wire wheeled it, then sanded it, then degreased until nothing came off anymore. Did the same to the valve cover, hamered it straight best i could again.
Next I put RTV all over the sealing surface on the head, didn't really care if it got rocker arms at this point, still tried to keep them clean though. Figured it any gets in there, the oil filter will catch it.
Then i put RTV all over the valve cover, installed the rubber gasket, then put RTV all over that too. Then i put it on, bolted it down to about finger tight then waiting about 15-20 minutes, then wrenched it down pretty tight with a small ratchet and wrench.
Ran a good while a day later after it all dried and no leaks so far. Finally... I think it's been leaking for about 10 years now at varying degrees of leakiness, hah. On the good side, the van and engine are all rust proof on that side now.