The first sentence on this link seems to back up the info provided above at least regarding the /8 designation, that it does indeed tell us it's a "stroke 8" 6-cyl engine:
http://www.geocities.com/mbz109/w108history.html
Also, your number plate 111.024.22 reveals the following:
111.024 (280SE... if it was 111.026, that would indicate it's a 280SE 3.5)
22 (first 2 indicates it's right hand drive built in Germany, the second 2 tells us it's an auto transmission)
remaining numbers should simply be the individual car's serial number.
I believe the Classic Center in Irvine, California will provide the original build sheet to you at no cost to totally verify your car's original specs. Have your VIN ready when you call. Their toll-free number is 1-866-622-5277 (1-866-MB-CLASSIC).
Please do share with us what you find out!