Mine how it already is (freshly restored), with 15 inch Bundts, somewhat lowered front stance (smaller wheel well gap), with possibly the manual/dual climate control system instead.
Was the w124/w126/w201 airbag wheel offered in the w123? I'm guessing so since other w123's with airbags had them from the factory but I'm not sure. Anyhoo, I'd like to get that steering wheel if only for the feel of it (smaller, but more solid, wheel).
It would also be great to have a rear electric shade if it was an option...?
If not then retrofit one...without cutting anything critical!