Well, I answered my own question with the help of Roger. In a effort to give back, since I found little on the web with pictures, here it goes.
This is a picture of the bailing plug, mine was rust colored when I started, but found it was aluminum (remember mine is a 1975, you mileage may vary), with the aid of channel locks, I twisted and pulled and it finally came out:
Note the holes in the side of the plug to allow water into the below housing:
Next is the plug pulled out and cleaned up, the best I could figure, there feels like an O-ring or something inside the hole, so the plug when pushed down seals and when pulled up stays. Not certain of that. There is a groove cut in the bottom of the plug, but I could not tell it had a rubber seal, so I wire brushed it clean. The inside of the plug has a bevel for the ball to float up to and act as a check valve in the case of the seal back leaking.......I guess.
I put my pinky finger into the venturi outlet hole underneath, or as it's called the bulb and pushed the ball up:
At least I'm not as scared of it. I'm going to find a 3/4" expanding plug