360 driveability problem

The knocking and pinging at low rpm concerns me. Have you checked to see if the "0" mark on the harmonic balancer actually is at TDC? The outer rings have been known to slip.

As Moper said, do you have access to the cam specs?

Is your PCV valve stuck open? That would create a nasty vacuum leak at low RPM's (high vacuum conditions).

The pinging indicates a high compression ratio. If the heads and block have been milled more than .020 combined, and if the correct amount of material was not taken off the intake manifold sealing surface of the head, the intake manifold will leak from the underside (inside the engine) and is very hard to diagnose.

If you have a propane torch you can just turn on the gas and run it around the sealing surfaces and see if the engine picks up RPM. This also works to diagnose a lean idle condition if you add propane to the intake horn of the carb.