Mallard, Thank you for picking up the discussion again. I love the term "The Sagulator" 
I tried it out just now on a rough guess on what I am using, and it gave me an "Acceptable" reply. Nevertheless, I have been spending a couple hours each day since my last reply disassembling the tabletop I put on the first wall two years ago and making sure all my brackets are level; front to back and side to side. To do that, I moved a bunch of stuff I don't need right now off the first tabletop and distributed it elsewhere. I am at the point where I will make a decision on what bracing to use on the front and underneath. The rub is I want to make the top in modules no longer than 48", when or if we move. That is all dependent on my mother-in-law's health. She lives across the road from us, is only 84, but in good health. We only plan to live here until she either passes on or has to go to a home. The rate she is going, we will be old ourselves by that time! 
Dave, Thank you for all the photographs! Your benchwork looks great! I like the narrow shelf below. Yes, I see the L-girder. I have used L girder before on a free-standing layout. I see you made good use of the 2x4s as well. I have a bunch of 2x4s I brought home from my Dad's that I can use where practical.
Jeff, I have a bunch of used wood some old and some not so old. Good advice as Mallard is saying you can't fix bad benchwork after you get so far.
Jim, The grade is to accommodate the passing siding switches being flat. Actually, the grade is quite similar to my favorite prototype, the Western Maryland's Blackwater Canyon grade that I want to model the feeling of some of the scenic features of the town of Thomas at the top of the grade, Parsons at the top of the grade, and some scenic features in between. Early on in this topic, I tested all my engines pulling reasonably length trains up a simulated grade, and they worked okay. Once I get to that point, I'll be testing again before anything final is put down.
Bob, thank you too, and thank you everyone for the suggestions and encouragement!!
