Like I said you got to get a vac gauge and break the circuits down to groups! it a hose, All it takes is a little common sence !

My w123 car is/was a 1980 European 230 - that was blown up by my neighbor’s daughter. I bought it for $500 at the age of 15. It does have a Ford power plant because a neighbor of my grandparents gave me that car free. So...

The w123 had two options...adjustable headlights, and a rear-heated window.
The Ford had a lot of options...one being power locks...so a little while with some aluminum, and a few bolts and wire cuts later - the car was equipped with power locks...albeit it the filler door...

The HVAC is manual...and I love it...both functionally, and aesthetically...

Power in my w123 is not a problem with the Ford power plant; the Eaton supercharger and the front mount air-to-air intercooler.

Jake