First of all - Welcome to HT.
My sister used to live at Fenn Ranger Station and I was there every summer. I killed my first bull in Unit 16 in 1986. Yes there are lots of bears and you need to be bear aware. That means good camping practices. If you do get a bear tag you decide to use your elk tag on one, be careful about black bear vs grizzly identification. There are not "everyday" grizzly populations in there, but every few years someone has an encounter, especially to the Selway-Bitteroot and the Montana border. I've encountered black bears right along the Selway. Rattlesnakes as well, but only down low. The first time I went into this country I was so "Bear Aware" that I was kitted out like Rambo. My kit has trimmed way down since those days.

If you shoot an elk DO NOT leave your quarters on the ground at the kill site. Move them and hang them. Black Bears steal more elk meat than grizzly.
I have never been in there late summer when we didn't eat grouse for dinner every night. Grouse (and bears) are crazy for elderberries that time of year. The trees will be heavy with dark purple clusters. I like a pump pellet pistol for grouse. A "Hush Puppy" pistol is legal to carry if you have the proper Federal forms on file.
I used to access Unit 17 off the Fog Mountain road. I've also gone in along the Selway and then up a specific drainage. There are outfitters on horses working the zone, so you need to figure out where they are not. It may not be about how deep you can go, but finding an ugly sanctuary pocket closer to the trailhead that the horsemen are blowing past. Be ready to go into the nasty stuff to find elk. Decide up front whether you want the pack out. This is vertical country. Google Earth can't show how steep it is. The burn layer and roadless layer in the OnX app will be your friend. Although the Selway zone fire map is almost solid with successive fires. Be sure to either go with a GPS chip or download all your maps for offline use because the is only cell signal randomly at the highest locations. Have a way to maintain your batteries.
Speaking of wildfire. Make sure you have plans B-Z lined up in case your primary target area is burning. Fires are common.
Good luck and keep us posted on your prep and your hunt.