Hanging rack in a WSM is great. You don't need to run both at the same time, but I suppose you could. You also don't need a stacker, but you might need to trim your slabs a little.
@Fritz...try putting the stacker between the bowl and the barrel (rather than the barrel and lid).
You don't remove the plate while the ring is lit (it's incredibly hot). Minion method to start with chunks on the outside is how I do it. I have plates and a basket. They can be run with or without the water pan. It really does even out temps especially when hanging and cuts down on the...
I have used both the $33 plate and the actual Hunsaker fire basket in both the 18WSM and 22WSMs.
They both work fairly well to even out the temps in the cook chamber. By that I mean, I haven't found the need to rotate meat that is hanging in there (they all come out pretty even). I also haven't...
Yes it was open. That bag came with a few other unopened off-brand bags. Everything was dry. As for the date of the bag...it's old. That bag came with a mid-late 70's black Weber 22 (that was maybe cooked on 2-3 times), a vintage flower cover in great shape, and a NIB full sized Weber table.
I have used the vortex basket in my dad's 18WSM and have a vortex plate for my 22WSM. Both work great. I am finding I no longer need to rotate the hanging rack because everything cooks more evenly. YMMV.
You don't see it too often on black kettles but older colored kettles you see it all the time. The cause is high heat (KettlePizza like Robert said used as a fire pit). You never see it north of where the charcoal grate sits. It's always from the charcoal grate area, down down.