https://turfan.bbaw.de/projekt/index.html#1
It contains this map ...
enlarged .... https://turfan.bbaw.de/bilder/Karte_gr.gif
One can detect Turfan in the big group in the upper right corner, below Turfan is the word "Qočo", which is the Old-Turkish form of Gaochang (identical also to to Chotscho and Idikutschari). "Qočo" shall be 30 km below in South-East direction from Turpan (more South than East, possibly something like 5 o'clock)
Somehow .... https://www.google.com/maps/place/Turpa ... ?entry=ttu