Quite a lot of beta coming here, so you might not want to read it if you don't want to know about moves as well as gear - not so much because it will spoil the purity of your experience but because I did the route about 5 years ago and this could probably all be just inaccurate enough to really sandbag someone (but I hope not). Great route.
I would agree with the idea that it would be good to have a shot at Finger Prince to give yourself some confidence for Iron Void. Despite being harder, Finger Prince is certainly better protected (and probably an even better route) – you will probably be able to get a small cam (tips/finger – old yellow metolius, old yellow HB or BD .3or.4?) in the shallow break next to the piton. I assume from the posts above that Iron Void has been upgraded to 23. I didn’t find the moves striking for 22 so I assume the grade is reflecting the pro, which I would say was fair enough.
You can get gear off the block – I had a 4 piece nest - to protect the start, which is pretty straight forward, and some pumpy to place gear just above that. Then things blank out a bit. In between some shallow nubbins of rock I was able to squeeze a couple of funny shaped nuts that I’d found but mostly it was a small array of less than thrilling bits between me and a larger, potentially very exciting fall for the move that I found to be the crux (which could just be because I frighten easily).
I backed off at this point the first time I went to the route. An awkward (tenuous balance that feels worse than it turns out to be) move reaching up and left and then moving your body to centre under the good holds on the flake leads to easier moves to a good pocket break on the right (good finger/tips cams – same size as above), which make the world seem a better place. Above this the climbing is steady without being too hard, although it could easily get pumpy fiddling in wires. There is plenty of gear in the upper half: it is small but it seemed pretty good; provided the flake doesn’t rip off, which doesn't seem too likely.