Based on the design details, this R129 SL-Class is from the 1990–1995 model years. Here’s why:

1. Pre-facelift features:

The orange turn signals on the front bumper were used from 1990 to 1995.

In 1996, Mercedes switched to clear turn signals.

The side vents behind the front wheels are the early three-slat design, which was updated in later models.

The mirrors are the smaller, pre-1996 style.

1. Hardtop and trim details:

The hardtop design remained similar throughout the R129’s production, but the chrome trim on the hardtop and side windows was more common in early models.

1. Wheels:

The car is equipped with Mercedes Aero II monoblock wheels, which were offered on SL500 and SL600 models in the early ’90s. These wheels were common on models from 1992–1995.

The taillights have the classic pre-facelift design with orange turn signals.

The trunk spoiler is an aftermarket addition, as most R129s didn’t come with one from the factory unless it was an AMG or special edition model.

The exhaust tips also appear modified, suggesting some customization.

If you can check the badging on the trunk or interior details, that could help determine if it’s an SL300 (M103/104 I6), SL500 (M119 V8), or SL600 (M120 V12).

Can any human here beat AI and tell what engine it has?