Designed in 1984, the R129 was based on the shortened floorpan of the Mercedes-Benz W12 and featured many innovative details for the time; these included electronically controlled damping (optional) and a hidden, automatically extending roll-over bar.

There were also a high number of standard features, with electric action for the windows, mirrors, seats and convertible top.

The rarest was the SL70 AMG, which had a larger-displacement M120 V12, producing 510bhp.

This monster of an engine later went on to power the Pagani Zonda – the motor itself is a work of art.

  AMG only made around 300 R129 SL-class cars, making them exceedingly rare, none more so than the SL70.

The build sheet (sourced from AMG) for this incredible car, states a build date of 17th January 1996.

According to the build data a 510bhp AMG M120 series motor was fitted (AMG records show this as being engine number 29), with a displacement of 7200cc.

Further AMG enhancements include the fitting of a sports exhaus...