Transmission oil change. Help please

[JdrifterCA]

hey guys.. umm i took out the drain plug. and drained the fluid. it was easy 5 min thing. now... how do i refill the transmission? I dont have a tool to take the filler plug out. lolz i had a air tool for the drain plug but is too big to take the filler off.(size is correct but just cant get to it). I read a few months back that one can fill the transmission up from the shift boot. i took the shift nob off, the leather cover thing. and now im looking at the shifter stick, and a rubber piece. What do i do now?