Block the 2nd Accumulator....The Inner bore is where the 2nd Accumulator piston rides, There is a feed hole at the bottom of this bore. Using a punch, Drive a .250" checkball into the feed hole below flush.
The arrow is pointing to the hole, I don't have a clear photo of the actual hole because I never thought I would have to tell someone how to do this... If you need a better picture? I'm in the middle of a 4L80E build & can snap a pic.
Block the 3rd Accumulator like I already covered in this thread.
Drill out the 2nd (Red circle) feed orifice out to .200"
Drill out the 3rd (Yellow circle) feed orifice out to .200"
********I DO NOT recommend doing this! You are getting the advise you want, Not so much what you need, When this trans breaks it's solely on you*********