Vince:
Your inquiry is actually quite complicated...identifying what is "original or "correct" for one of these cars is not so easy at times.
As just one example, I stated a thread asking about a Brake Booster vacuum tube which can be black mesh covered or clear plastic. Took several replies to settle which style is correct for a 1969 car.. and there are transition cars where the answer is not certain.
"Correct" for various Pagodas is complicated by production changes that were made during the years of production. Some changes like Old Style side mirror to New Style mirror are known from vintage MB documents as to a specific VIN number but even here Mercedes was known to install the "old" part after the change date to use up the parts inventory. So it is possible that some later VIN number cars had the out dated part installed at the factory.
Production change tables are included in the books: Original Mercedes SL by Laurence Meredith, and the "Bible" for these cars: Mercedes Benz 190 SL - 280 SL by Gunter Engelen (available in German only).
That said, compared to let's say, Vintage Mustang owners, Pagoda people are not nearly as fanatical about having the perfectly correct part. The Mustang guys get down to the code numbers on top of each bolt.
Some Pagoda parts are NLA (No Longer available) and must be sourced from donor vehicle, parts dealer, or replaced with a reproduction if available. The repros are generally of good quality and nearly impossible to tell from the original.
Using the Mercedes Classic Center as a source does not always solve the quest for originality as some currently available MB parts are later design replacement parts that do not look like the original.
Further complications arise from modern safety rules where tubing, electric wires, and similar have required printed specs and warnings stamped along the item . These stampings are not on the original parts and are a dead give away that a part has been replaced. Judges are not supposed to deduct for added or changed safety items so stamped tubes or wires are not usually an issue for losing points at a Concours judging but some obsessive Pagoda owners try to remove the printing along the tubing or search long and hard to find unprinted items.
A well known indicator of original fenders is a small mark on each fender next to a "pointer" in the chrome ring of the headlight. The fender mark can be added to a repro fender and is no longer a reliable guide to fender originality.
The major components of the car including the engine, transmission, and the rearend Pumpkin have stamped numbers that coincide with the numbers on the Datacard for the car. In that way, the originality of these parts can be determined if that's important to the owner. No one checks these numbers so only the owner and the mechanic will know about changes.
Some parts of the car body (hood, soft top compartment cover) have numbers stamped into them which match part of a number on the Fender Tag of the car. These parts were made large, then cut to fit a specific car, removed then rematched to that same car later in production.
Variations in cars also resulted from local government regulation. So a car sold in Italy, for example, would have a small round orange light or reflector on each front fender. These are found on no other cars. USA government regulation is the reason we have USA version and Euro version cars with all the differences between them as discussed on other threads here.
Some items ordered for the car and shown on the Datacard were actually installed by the local dealer not the factory. These might include the radio, antenna, air conditioner, floor mats, and more. Local dealers were not always perfect in following MB guidelines when installing these items so variations in parts and placement can be expected.
Not sure this is what you were asking about but someone may find it useful.
Don't forget to enjoy the car...originality is just a small part of Pagoda pride and satisfaction.
Richard M, NYC
