350 Turbo puking fluid when parked a while

My car has puked tranny fluid ever since I got it running. If I drive it once a week or so, it might leak a bit, but not very much. If I let it sit a couple of weeks, I end up losing a quart or more. Someone told me it was probably the torque converter leaking down. Anybody ever have one do this, and have any ideas on how to stop it? [S

May have to get a large catch pan and put under it. It makes a heck of a mess in my carport shop.....

Look to see if it is leaking out of the shift shaft seal. I have one that is leaking just like you describe. Bought a tool to change it with out draining the trans.

A 350 is a leaker.

The manual shaft seal is sometimes the problem. When you replace that little seal take a rubber o-ring that is for a transmission of some kind
which fits snug on the shift shaft and use it. Then put your new seal in
tapping it down until it feels bottom. That will stop leaks where the case has
some wear. That even a new seal by itself will not fix.
The dipstick and passing gear downshift cable is another silicon both even with a new seal . It will lubricate the seal for assembly taking away some of the chance of nicking the new seal and provide more sealing when dry.
The accumulator cover also is a problem for a transmission not recently rebuilt, a used one. In the car a tool is often needed to replace it and check for a broken spring while you have it off. I made my own tool.
In an old transmission the pump o-ring may start leaking. Even though a 350 wasn't bad on that.

The plastic speedometer gear will actually wear the aluminum housing. Replace both with new seals even though some wear can be handled by the generous use of silicon when the cable is put on.
I bought an old car that the speedometer cable was off of it. It was leaking badly at the speedometer and I needed to drive it for a while before using the engine. I took a bottle cap filled it with silicon and screwed it on the the threaded housing. I didn't want to kill a cable just to stop the leak is why I did that.