Best road for trip from Sji-Hsih to Taoyuan (fuhsing,dashi)

Someone please advise

Friends are travelling from Sji-Hsih to Taoyuan by car. We want to meet up with them in the mountains beyond Dashi at Fuhsing where the old Chang Kai Shek summer villa (the youth activity centre) is or somewhere around there. I have seen signs to Taipei up there and want to know what the best way for them to go would be. It’s either that or they hit the highway to Taoyuan City and pick us up. I just think with the traffic heading back and forth there might be a quicker way for them to go there and back directly.

Can someone help me out?

i also need contact details for the Youth Activity Centre at Fuhsing. I know they had nice decent cheap rooms with a view for about 8 people the last time we checked. Can anyone confirm that? Anywhere else that might be a good place to spend a night up there?