Updating to the look of the 1990-1995 W124's takes quite a bit of money. The following parts are different:

Exterior appearance:

1. Body colored bumpers (impact insert still black on 1990-93 models) with chrome moldings at the top
2. Large flat side moldings with chrome insert (fender, front door, rear door, rear quarter panel)
3. Body colored mirrors
4. Rear trunk filler panel
5. Rain rails, rear windshield molding, and molding lateral to rear door triangle window are glossy
6. Body colored side skirts

Interior:

1. Leather seats have a different stitching pattern
2. Door panels have wood trim inserts and models with leather interiors have pleated leather trim
3. Dashboard has wood trim
4. New ashtray with smooth push-to-open operation
5. C-pillar trim panels have cutouts for auto height adjustable rear seatbelts

Note that 1994-1995 W124's will have bumpers that are entirely painted, new hoods with flat grille, and new trunk lids with chrome trim. There's probably a few other things I forgot, but those are the "major" updates.