Question on different part numbers for the A/C pushbutton control unit in the center console...the one in my 1987 190D turbo is 201-830-07-85. This part number is NLA from MBZ. I have a seemingly identical pushbutton control unit from a 1992 190E that has the part number 201-830-09-85- it is identical in every way to the unit from my 190D (all pushbuttons are the same with the same functions and has the same electronic attaching pins) except the temperature roller wheel in my 190D is printed in celcius scale where the 190E is in Fahrenheit. Are they interchangeable?...I know MBZ had slightly differing temp stickers over the years for otherwise seemingly identical control unit...some say "max" or "min" at the ends of the scale where others just have a "dot" at the ends of the scale. I'm pretty certain MBZ would go to the trouble of having a new part number for each of these "cosmetic" differences even though there are no functional differences..thoughts?

J.G.