I meant to include this in the last post…when I was working out how big to make the gravel pad (and before I do most stuff), I always like to do a little sketch before I start doing too much work, to make sure I get everything right. It’s really easy to miscalculate or mis-measure, hence the old adage “measure twice, cut once.”
I took a picture of my workbook, I guess it just looks like the scribblings of a madmen, but just thought I would show a little insight into my process of doing stuff.

You can (perhaps) see that I worked out, I’ll see about 11 cubic yards or 22 tons of gravel, to create my level pad (50’1″ x 9′ x 8″ thick). This should give me about a foot of extra pad beyond the extents of all the racking and concrete ballasts. It also means I’ll be shoveling out about that amount of topsoil, or perhaps a little more, to get down to the bedrock. A good honest workout, to be sure.
You are my favorite madman, so I love to read about how you do stuff. Looks like more work in your future. Thank God the weather’s good!