'57 T'Bird

I have a 57 T'bird with automatic transmission. Transmission has been out two
times over past 5 years and performs fine. My problem is that when idle is at
3-5 hundred rpm, and I shift into drive, the engine dies. It feels like it is under
such load it can’t run.  I have to run rpm up to 1000 / (aprox) set the parking
brake, shift into drive, and idle down to a point just before gen. Light starts to
show, and engine starts to die.  Of course when I shift back into neutral, rpm
runs back up, and shifting back into gear causes hard jerk. Shifting into
reverse is worse than into drive. Fluids are all good, engine runs great, and
trans. Works great while driving. Any ideas will be greatly appreciated.