Having to use a hammer is never a good thing on a electric connector. (Did you have trouble removing it?)
No, didn't have trouble removing it. A combination of pulling from the inside and pushing from the outside popped it out.
I wasn't hammering on the electrical connector exactly. This piece is made up of a plastic outer "tube", and a rubber inner cylinder, which the wires go through. The O-ring sits around the plastic outer piece. So this isn't a male/female electrical plug, just something that holds the wires, and keeps the transmission fluid in. The whole thing is about 1.5" - 2" long. The screwdriver was pressing against the rubber part of the plug, not the plastic part, and was not pressing against any wires.
There's so little space to work in there, I couldn't think of any other way. We tried many different things to get the plug back in, but nothing would work. There's barely any room to pull the wires from the outside, and barely any room to push the plug from the inside.