2 weeks before things I mentioned: dealer (different from those two dealers mentined above) service advisor. He was supposed to show my car to parts speciallist or the body shop operated by that MB dealer. But he ordered roof rail which is for wagon though my car is sedan. After several call with him, I decided not to deal with him anymore. His manager agreed to remove all parts oder from my invoice, but the charge amont indicates that the roof rail was included. He said he would fax an updated invoice, but he did not. I called the dealer a couple of times, but they consistently connected me to voicemail. I did not get any reply from them. I sent a mail to my credit card company.

First body shop -> first body shop cancellation: 3 days

dealer parts order -> dealer parts pickup: 1 week

dealer parts pick up, dealer operated body shop, back to dealer, other glass shop, other dealer: in one day.

Strangely, the last dealer told me to pay at the time of order, while the previous dealer told me to pay when I pick up the parts.

By the way, shall I let the glass shop work on my car, or should I find a different indi body shop or other glass shop? The glass shop told me to get parts myself, and that dealer's parts department knows what is needed.
Dealer said that those who do the job should know the exact parts.
Dealers and body shops say "Go to glass shop for those jobs".

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1992 300D 2.5 turbo diesel. 319 k miles.
124.128 chassis, 602.962 engine, 722.418 tranny.