With respect to Photo #4, I never thought about marking my Quik-Lok amp stand! Every time I set up I end up altering the height because it's not perfect. I assume that is just a couple of pieces of white tape, or is it white-out type material?

I do realize that due to the different types of rooms being utilized that one amp setting is not optimal for all venues but in my case it doesn't make much of a difference.