Here's a little bit of a twist. I was just out in the yard disassembling the stand. I took all the grinder apparatus off it as well as the top plate. I expected the stand to be FULL with concrete. Instead, peering down inside the stand I can see it's only 10" - 12" from the bottom.
The problem with leaving it the way it is - the concrete is not flat so the stand rocks a bit. I'll probably put feet on it anyway, but I'm a, "strip it down to the bare metal and refinish," kind of guy. So the concrete has to go.
I had a small acid spill on the back patio a couple years ago (don't ask). Four of my paving stones simply disappeared. I may give the acid a try - a side benefit will be rust removal. And there's plenty of rust on this beast.
I may put this on a scale tomorrow just for giggles.