You can't because the part numbers don't match, or because they physically won't fit?

If you're going to replace the struts on the 124 and throw the 124 HD's away, I would experiment with putting them on the 190D. The 124 and 201 HD's are very very physically similar, they might well fit on the 190, and the ride might not be too harsh

I'm assuming that because the Bilstein part numbers are different, that they are different struts/shocks. Without having them side-by-side and a lack of specs available on-line, it is difficult to tell the size differences. Then again, there may be internal differences due to the different weights of the respective autos they are designed to fit.

I'm most likely selling the CE and wondered if I could save a few bucks by putting the Bilsteins on the 190D. The original struts/shocks would go back onto the coupe. They have been sitting in the garage for quite a few years now.

Then again, the 190D is so awfully slow, painfully so, that I might just keep the coupe. The 190D is the perfect inner city, urban car, but not very well suited for long distance driving, especially in hilly terrain during rush hours. I'd forgotten how slow and underpowered diesels are. My last one was a stick 240D that I got rid of about fifteen years ago.

__________________
-Steven

---
1959 190b, totalled
1968 220D, sold
1969 230/8, sold
1980 240D manual, gave away at 300k (stupid me)
1985 190D 2.2 manual, gave away to a youngster
1989 300CE, sold when I retired - major regrets

Man, I resemble that remark!
I love my 190D. Plenty fast enough for me. Much faster than the Peugeot 504Ds I used to drive in the '80s.

__________________
1987 W201 190D