Ok. With the help of Roberts drawing I got it repaired. I was going to take pictures, but my hands were filthy. I can give a walk through so if anyone encounters this issue in the future.
To access the grass door I tipped the lawn mower on its right side as per Robert's suggestion as well as unplugged the spark plug.You will first need to remove the blades. Then there are three retaining plates that are each held on by two bolts each. The main thing here is pay attention where the one plate goes that's held on by two bolts that are much longer than the other four, it will just make reassembly a little easier. Remove all of the bolts and retaining plates. Now you can remove the door.
On the door there is a carriage bolt that goes through a retaining plate on the bottom side and is held in place by a washer and lock nut. It is this lock not that sits in between the the tines in the fork at the end of the grass door lever. It is not attached to the fork as I first assumed. The nut was so corroded and rounded I had to use an angle grinder to get it off. In doing so I also damaged a spacer that went between the bolt and nut. I bought a stainless carriage bolt about an inch long, along with a fender washer and lock nut. I figured between the metal washer/retainer on one side of the door and a fender washer on the other I could get around replacing the spacer. Then it was just a matter of replacing the door and ensuring that the lock nut was placed between the tines of the fork. I then replaced the three retaining plates and then tested the door's operation. Then satisfied with the operation of the lever replaced the blades and reconnected the spark plug.
Let the mower sit upright for an hour or so just to make sure the oil had settled and then cranked ti to make sure everything operated ok.
I used a 3/8 impact wrench that made the job much easier than wrenches. If I had had the bolts or correct parts for this repair I could probably do it again in 15-20 minutes.
I started to order all new replacement parts (door, bolts, nuts, spacer, fork), but figured I don't use the door that much and it lasted almost eight years although all of the parts including shipping was about $502. Figure I'll wait until it wears out again and do it then. The reason I mention the fork is that it was pretty rusty.
Anyway, if you have this issue don't hesitate to tackle it yourself.