292 using/leaking a quart every 30 miles

[Elephanthead]

What are the usual suspects for this much oil leakage/usage? It looks to be a later model 292, electric choke, hei distributor, where is the oil leaking out of? does the rear main seal on these leak that badly, side inspection covers, valve cover? Should I buy gaskets or use the right stuff? I don't notice any smoke and the thing runs like a beast, just always needs oil. The emission stuff is not plugged off or hooked to a pump if that makes a difference.