I did it last weekend for the first time. Look for some posts below by dvanhouten under the subject "Jackson WY / Snake Rive Boating Info" to get info on the run. Not sure if it is still flowing that much. We did it a touch below 800.
Directions to get to the put in and avoid the first few miles of flat water: Get into the town of Felt and take a left just past Badger Creek. I think it is "1000 St". Follow that for a few miles until it takes a sharp right turn. Do not take the turn but go straight down the double track through the potato fields (careful on the right hand muddy corner, you WILL slide into the fields).
The take out is the big hike out, not the put in. Well, maybe 1/2 hour TOPS. To get to the take out, follow above except follow the sharp right bend turn to the end to the plant. The river take out is an obvious dam. Take out on the right by the fence, jump the fence and hike up the access road. Just before the road drops down the hill there will be a little trail to the right. Follow that up to a locked gate. Jump the gate and the take out lot is 100+ yards up the road.
The JH Kayak school has info too http://www.jhkayakschool.com/
Call with questions.