All of the text refers to the conditons at the time of printing. The manual is directing one to the climate control manual that is for the 124 body. That manual is included on the 124 CD.
The original print manual is 3/8 inch thick. The only thing that one is directed to the 124 manual is for the testing of the sensors. The locations wouldn't be the same as the case is different for 126 versus 124. The way the system works is the same.
Bosch Master, ASE Master, L1
33 years MB technician