Oil Leak I guess

[jolobo64]

Got a 64 chevy c10 350 engine and tranny seems to be from mid 70's. She looks good and runs good but I notice when I return from a drive there is a small oil drop in the driveway. Worst than that I can drive about 40- 50 miles and I am clearly a quart low. Thought it was valve cover or intake gaskets, changed those. Still same problem. There is no smoke when driving , of course early morning there is very light( not bluish) white smoke, that seems to be normal on any car just starting up in the morning.

Sitting idle no oil leak, Oil pan gasket is my next task, just wondering where can that much oil be going? Oil is clean, once again no smoke to indicate its burning oil, but I am lost for ideas???