Jonathan:
Oh my God!... Breathe deep and enjoy the Hills around you.
Go play the tables at the casinos.  Take a day or two and relax. Rent a car
and get away from the Westy. Your intellect  will overcome the
problems that the Teutonic engineers gave us.

It's running rich... you have been, I think, correctly playing with fuel/air
only... But how's the spark?  Is the distributor on good and tight?  How do
the rotor and Hall effect connections look? Check the Hall effect ground on
the left side head.
These all operate fairly well at low RPMs and only show at higher revs. I
know that you said they're new but did you recheck them?   How about the
intake boots?

>Finally, No I have not changed the fuel filter because in the many
>stores I have been to, nobody has one

... You can jumper across the filter with a hose and eliminate this as a
source of your problem really quickly. However, rich doesn't equal fuel
filter.  Rich equals air or O2 sensor.

My $.02... wishing you the best.

Stephen