Just before Six Lake Basin below Smith Mt lookout and right at the top of Deep Creek there is a trail head. That trail goes around Six lake Basin down through the headwaters of Granite Creek and up into Horse Heaven and ties into the Rapid River trail. It's about a 4-5 hour ride from that trail head to Horse Heaven. Granite Creek is the division between unit 18 and 22.
It's a little quicker from Six Lake Basin but then you are getting the trucks down in there and have to climb up and out and with a dump of snow could get crappie. Get a topo and look. There is a lot of country in there. There has been two bucks that I personally know of that have been in Monster Muley Magazine about 12-15 years ago, 3 years apart, taken at the top of Granite Creek. There has been 5 bucks over the years taken in this general area that have made the book. Everything is there. Steep rugged country minimum pressure so bucks can mature.
Don't overlook the Rapid River trail. It starts just south of Riggins and climbs into the same country. You would want to break off on the West Fork Rapid River trail after a few miles up the main trail. Quite a bit farther but the trucks would be safe down low.
Get a topo and look...lots o[FONT="]f possibilities !![/FONT]