I cannot get that damn plug by the pass side cv joint to come out for the life of me

it would help if GM acutally used like hex plug but they used some weird plug in there.
so now i'm SOL as to how much atf to put in

can anyone gimmy a helping hand and tell me how much to fill it completely? this is WITH a filter/pan gasket change and the trans was completely empty!
thanks!!!
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** Flat Broke Racing Inc.**
Says in the owners manual. I'd check but don't have one close by.
12 qts when completely empty

The one, the only, ME.