SWEET!! tall enough for us normal people almost! ;-)
You can check hardness of stuff with a good file.. if the edge of a good "mill" file cuts a piece easily, the piece is usually soft or not yet heat treated. If it "screams" or "sings" off the piece, its harder than a preachers dick in a ..... well you get the idea.
You can use that to check areas around welds, or welds themselves. If it gets too hard, watch out! There's a whole bunch of hard vs tough vs strong vs black magic I can't remember anymore... but it matters sometimes.
This project isssssss great!