You do not say what, if any, parameters you need. I “assume” you want to avoid gravel and you are self-contained. If so, consider continuing south on US-93 (from junction with MT-43 on TransAm Route) to Arco. A remote way would be to take ID-28 from Salmon to ID-33 then points east.
Then take ID-33 east (via Rexburg, Sugar City, Tetonia, Driggs, Victor, Wilson, WY to Jackson. Take US-191 from Jackson to Rock Springs.
From Rock Springs you can take Interstate 80 (blah, but legal) with its services east to Rawlins, WY and reconnect with the Great Parks South Route.
Or for a much more remote experience, from Rock Springs take WY-430 south to Hiawatha Road to Baggs, WY to Craig, CO (really really remote) OR take WY-430 south to CO-318 then east to Craig, CO (just really remote) and then continue east to Steamboat Springs and reconnect there.
If you go via Rawlins, I highly recommend a detour from Saratoga, WY to Centennial along WY-130 then south on WY-11 to Fox Creek Road (8 miles of decent gravel road) to Woods Landing/WY-230. Go south to junction with CO-125 where you reconnect with various ACA routes.
Enjoy the ride!