If the Green rules are the same as the Colorado River side (I'm almost sure they are) a groover will be needed. Also, you will need a shuttle if you are just going down to the Confluence. You could also float to Mineral Bottom, and take out there. At least you don't have to pay a jet boat to take you back up. You will need a permit if you go below the confluence, which is call in. Shitty thing is, when we did ours, the reservation office was closed in moab, so we had to go all the way to Island in the Sky. That is a long friggin drive to get a permit. I think TAG will probably be running their jetboat by then. I don't know what they charge, I have a good drinking relationship with the dude that runs it, and am priveledged, as they call it. It should be starting to shape up by May.
"What once was a river. Now a ghost." Edward Abbey