Suggested routing
A common road-trip pattern is Guwahati toward Bhalukpong/Tezpur, Dirang, Tawang and Bomdila before returning to Guwahati.
Vehicle choice
A 4x4 can be useful for confidence in difficult conditions, but vehicle choice should follow current road status, group size and driver experience. Do not assume every tourist sector permits an outside rental vehicle.
Permits
Indian visitors to Arunachal Pradesh generally require an Inner Line Permit. Check the official Arunachal eILP portal for current validity, fees and entry conditions.
Weather and buffers
Build spare time into the itinerary. High-altitude weather, road work and local traffic controls can change a planned driving day.