This 1969 Mercedes 280 SE (W111) arrived at Mechatronik in Pleidelsheim, Germany for their M-Cabrio 550 transformation. The work involved a body-off restoration while upgraded the powertrain and suspension.
In the engine bay they swapped a 5.4 L M113 V8 capable of 354 hp and 510 Nm (376 lb-ft) of torque. The drivetrain uses a NAG1 five-speed automatic transmission and Mechatronic’s limited-slip differential.
Mechatronik improved handling using KW Automative lowering springs and shocks. Stopping the car are W126 two-piston calipers with 286 mm rotors in front and W111 two-piston calipers with 273 mm rotors in back.
Mechatronik decorated the body in DB 180 silver gray metallic paint and freshly chromed trim. The finishing touch is a set of 15×7-inch wheels with 205/65 tires.
On the inside the company added new black leather and 301 dark gray carpet. The dash and center console are adorned in Walnut and Burl wood. They also installed a modern sound system along with power windows and locks.
Source: Mechatronik
That is not a solid axle, nor did MB ever make a 5.5L M113
Thank for catching that. Article updated.