It takes about 10 small taps with a 10" forged flat-head screwdriver (and hammer) to get the tab pushed in. About 1 minute of work.
Do a few taps at a time then turn the wipers on then off and see if there is engagement. If not do a few more taps and retry.
Now I need to go to GM and purchase some of those plastic fasteners that I drilled out and a new passenger air filter. Then I will put the wipers back on the bolts seemed to be (lock-tighted blue) also.
July 6th:
I put everything back together and it seems to work. You may need some type of prybar (used a nail puller prybar) and a piece of metal (I used a large screwdriver and a piece of cardboard underneath) as a prying surface to get the wiperblades off.
The plastic fasteners are hard to get off because they are the expansion type. The screw must come out before the seat. Drilling into them and pulling out is the easiest way to remove them, but then you wreck the screw face somewhat. These will cost you 78 cents a piece at GM. The one with the flathead surface will actually screw out and is not an expansion screw. The white one on the wiper motor cover (underneath the wiper cover -3 covers total) will need to be pryed out because it's not an expansion screw.