If the middle fork is already at 6.75 then it is almost topped out. They dont have a huge snow pack up there this year, it will be down to 5 feet by then, unless there are some crazy rain storms.
We put on last year on May 28th at about 6.5 feet. The first day was pretty hectic for the raft guys, we did flip one raft in murph's hole. The rafters need to keep an eye out for a big left had turn in the river, if you stay far inside you will sneak right by it. All our rafts went straight through the middle(out of surprise) they all got surfed, but only one flipped. One of our kayakers was paddling into it for some crazy surf. We also flipped a boat at velvet. Good times, I am jealous its the first year in three that we missed out on a permit.