Barry Taylor has used it for his shop car for many years, it's a screamer, though he now uses a W210 6.0 wagon for his shop car.
I think if you want a super "hot" W123, this one right here's the one for you. It's been collecting dust for several years, but it should clean up beautifully. The AMG conversion was done in Germany, but the car is California and 50 state legal, and what is amazing, he has always run it on dealer plates since new, in 1984, so whoever buys it would be its FIRST registered USA owner.
I took these shots last month when Barry let me into his second warehouse.......
(disclaimer: - I have *NO* personal connection with BTE or any personal involvement or interest whatsoever, in the sale of this car. But here it is.)
This car sounds like a 427 Corvette at idle, and when you floor the "go" pedal, it GOES !!!!!!!!!!!!!
A true, unmolested, uber rare, pre-merger, AMG wagon, complete down to the metal AMG build plates on it.
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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)