904 trans leaks

6 quarts should be safe, depending how long the pan is off.
(Less than an hour)

There are a lot of places they can leak that look like the pan is leaking, so try to be sure about that.
1. Dipstick tube
2. Shifter shaft seal
3. Throttle pressure rod seal
4. front band adjuster nut

Those A518/42RE,42RH trans pan gaskets with rubber over steel are killer if you can do it.