For a privileged clientele blessed with unbounded checkbooks during the 1980s, AMG would entirely transform any late-model Mercedes-Benz product with greatly improved power, handling, aerodynamics, unlimited interior luxuries, and attention-grabbing cosmetic accoutrements. Each car specified by an AMG customer was bespoke, replete with à la carte options offered from the company’s wide-ranging catalogue.

Until 1985, AMG’s most impressive engine upgrades included displacement bumps up to 6.0 liters, which were also surmounted by a top-end power kit featuring SOHC cylinder heads with solid mechanical valve lifters, custom-ground camshafts, and a variety of supplementary speed parts.

This exceptional and well-documented German-market 500 SEL AMG 5.4 was ordered new from AMG (via the gray market) by a well-heeled enthusiast from Scottsdale, Arizona in early November 1984. It was extensively modified through the “AMG Southwest” licensed facilities of Achim Brose in Bonn, Germany, and then brought into the United States via the Port of Houston. After its federalization by a licensed importer, this AMG SEL was first registered in Arizona in April 1985, although records in the car’s warranty book may indicate that it was mostly domiciled in Houston, Texas during its early life.

Assuming a base price of nearly $52,000 for the 500 SEL itself, another $52,000 for the extensive AMG modifications listed on the original invoices, as well as a sizable chunk of change due for importation and federalization costs, the final cost of this AMG super limousine quite inarguably exceeded the price of a brand-new Ferrari Testarossa, Lamborghini Countach, or Porsche 911 Turbo.

Accompanying copies of its original AMG invoices, coupled with inspection at time of cataloguing, confirm the car’s full suite of desirable pre-merger upgrades includes the 5.4-liter displacement engine with top-end power kit, AMG by Bilstein suspension and chassis reinforcement, and Gen I aero kit with a set of color-matched 16x8-inch wheels.

The standard S-class interior was clearly not luxurious enough for the original owner’s taste, and AMG fitted an outrageous volume of additional leather which covers the doors, dashboard, steering wheel, gear selector, center console, and door pillars. The true pièce de résistance of this extravagant 500 SEL 5.4—notwithstanding a set of rear privacy curtains— is the gold-plated Clarion G80 hi-fi stereo rack sound system with accompanying 240-watt amplifier mounted in the rear deck.

In May 1989, this super saloon passed to a new owner living near Pittsburgh, Pennsylvania. Since then, it has remained local to that area, with a short chain of just four recorded owners. Now showing just under 31,060 actual miles at time of cataloguing, this 500 SEL AMG 5.4 would be a tremendous acquisition for any Youngtimer aficionado.