Have run multiple times at this level. did it three weeks ago at essentially the same flow. It is do-able much lower. We did it a few years back at 375 in over-loaded duckies. Ranger says he'll run it down well below 400 in his raft.
I would leave a thing out or two, but saying that, we brought way too damn much on this past trip. I would just drink most of your beers and water and burn all that firewood at slickhorn so the last 12 miles don't suck as much. Stay in the flow.
8 foot and Government are worth scouts for me. Government is real bony so get a good look, there isnt a whole lot of options down in there at that cfs.
Enjoy your trip.