to much fluid?

ok, i have had my engine and trans out to do work on them, hell of a time getting them back in with the headers.......anyways i am at the point where i am filling fluids, sent trans to shop for rebuild and engine got a good draining as well. oil, water went in fine. but when i was adding trans fluid, car not running, after several quarts, around 7 it started gurgling a little and then fluid started leaking out between engine and trans.....any suggestions on what i did wrong? not running engine cause the fluid to just fill up the res to much or something? i was told trans was dyno-ed, (have the sheet) but they told me they drained the fluids as well, any help would be appreciated.

Sounds like it was trying to vent itself until it started coming out the front seal. How much fluid leaked? Once you fire the car up and put it in neutral, the fluid will fill the converter and you should be fine. What size converter? With a deep pan and 8” converter, 7 quarts is usually enough. I typically start with 6 and then add but that’s just preference.