Thanks for the link to your resources. I've looked, but none of the models look like the one I have. I've attached some photos for you to see.
I browsed thru model 1432 (year closest to my 1995 E280 (w124 plus mine has also been integrated with an Alpine 6 Cd changer as described on the intro page). I didn't look at 1492 or the 1692 as they both use a 5 digit code and is probably newer models). The operation guide for the 1432 on:
Recoding Sequence: says "To recode a radio, follow this procedure:
1. bla bla bla 3.Enter the first digit of the radio's antitheft code ......... . The word CODE will disappear and the first number that you have entered will be displayed. 4. Enter the rest of the antitheft code. Each number will be displayed when it is keyed in. 5. When all four antitheft code numbers have been correctly entered, radio operation will resume. The station stored at push-button 1FM will play.
Incorrect Code:
If an incorrect antitheft code digit is entered, continue to enter numbers until four are displayed. The word CODE will appear again. The system allows two more recoding attempts. After the third incorrect attempt, the word WAIT is displayed. A period of 15 minutes must pass and the word CODE must again be displayed before recoding can be successful. The radio must be left ON during this period. This measure is meant to prevent a thief from recoding the radio by randomly entering numbers. If the correct antitheft code has not been entered after three separate attempts-and therefore after two 15-minute WAIT intervals-the radio will lock for 24 hours to prevent any further recoding attempts. The radio
must be left ON during this period in order for it to reenter the CODE mode.
Based on the above, I've entered hundreds of 4-digit codes. After entering each 4-digit code (incorrect ones of course), the word CODE does not appear again as described. Instead, the 1st of the 4 digit code that I'd last entered will blink. I can then proceed to enter other codes. The only time the word WAIT appears is if I press the up or down "triangle" (the "Tune" buttons in the 1692, except that instead of facing left and right, the "arrows" face up and down). And then I have to wait not 15 minutes, whether 1st or 3rd time, but hours. I read somewhere 2hrs something minutes ans some seconds.
Nobody in my neighbourhood has responded to my request yet, so it looks like I'm going to have to resort to approaching total strangers. 
Merry Christmas and Happy new Year everybody.
Phillip