Don't stress. It was a complex used car and you were trying to get a handle on everything at once; even the seller was questionable, it seemed, and the registration issues, the gas filler flap, missing records, overheating, impossible lic. plate brackets, all of it, now another trip.
Consider it deferred gratification, just some things to square away, but those things are heaven on wheels when they are running well.
And, they will ALWAYS look good. A testament of the discernment and good taste of its owner.
They are assuredly NOT some ugly Hyundai, with interior of plastic cheap hell.
It is old fashioned German quality, the feeling of riding in a car hewn from stone and that is fast, comfortable, safe stylish and everlasting.
You will have another Mercedes day. I guess I will, also, tomorrow. goodnight
(also: about Hood pads) see
560SL hood pad
And on a somewhat downbeat note,* please* be sitting, before looking at this SEC picture/story.
http://www.benzworld.org/forums/mb-safety-testimonials/1318365-126sec-easter-weekend-fatalities.html
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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...
1995 E 420, 170k "The Red Plum" (sold)
2015 BMW 535i xdrive awd
Stage 1 DINAN, 6k, <----364 hp
1967 Mercury Cougar, 49k
2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive

(sold)