Hello,Mr.Fred.
The cable car fare is 35RMB for a single trip and 60RMB for a round trip. You can take bus bounding for Mt.Qingcheng at Cheng Du Xin Nan Men Passenger Station and Cha Dian Zi Passenger Station. The bus fare is 17RMB and the estimated journey time is 2 hours. I have been there. What you said is right. Two hours is far from enough. You should spend at least half a day. Mountain climbing is not an easy task, use cable when it is necessary.
Good luck to you!