Just looked at the pictures, it appears there is no trap oxidizer. I have only seen one, on a 1987 300D Turbo, and the trap was a fairly large item, nestled between the engine and right fender.
I have been watching and pricing 300SD's and SDL's for the last couple of months as I plan to get one. 300SDL's with comparable mileage in California are fetching $12,000+. There is a 300SDL posted in Trader On-line, just under 100,000 miles, they're asking $57,000, a bit unrealistic.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.