Well, replacing a fuel pressure regulator on a 560SEL is a DIY.

Only one trip to the auto parts store mid-way into the replacement: for a can of PB Blaster, a chemical I can now highly recommend over Liquid Wrench. One of the nuts was siezed up quite hard (it had only been sitting there on top of the engine for 14 years after being put on in Germany! haha!) and PB Blaster got it loose.

Other results: car now idles so quietly at stoplights that I can't tell the engine is running. Also, the gas fume smell is now gone.

I love pre-1995 Mercedes.

Cordially,
OneTwoSix
Current: '89 560SEL, 135K.