I'd take hwy 89 out of Truckee toward Sierraville. Then onto Graeagle. Hwy 49/89. Hwy 70 to Quincy. And don't miss the turn back onto hwy 89 toward Lake Almanor. Then hwy 36 at the T to Lassen. You'll have an awesome view of Lassen along Lake Almanor's west shore. Adding a few miles, you can pass the turn to Graeagle and continue on hwy 49. Then take the Gold Lakes hwy to Graeagle. There are some awesome views of the Sierra Buttes. Coming through Quincy stay in the left lane when it becomes one way in old town. Loop back around to see the town.