I finally got all the seats off. I did have to remove the drawer insert under the sink to remove the 2 back pad on both sides of the sink. There is a strap on both sides that must be removed. To access the straps, remove 1 of the cup holders and remove the black cover, 4 screws. It helps to removing both drawers to do this plus it makes it easier to remove the insert. Then carefully cut away the caulk on both sides of the insert. Cut the caulk off the top by running your utility knife along the top edge of the insert. Once that's done carefully use a large screw driver and/or pry bar to work the sides of the insert free. Once the sides are free, carefully pry the top corners one side at a time. With the drawers remove from the insert, it makes it much easier to work the insert back and forth to free it and easier to handle when you remove it.
The seat bottom on the engine cover was much easier than I thought it was going to be. There are 4 pop rivets on the front of the seat that can be drilled out by lifting the cover to access them. Once those are out, the rest of the fasteners, 6, are plastic push pins that simple pop out as you lift the seat.