HETPE3B

Since I need quite a few parts for the front end of my w209 I'm considering if I would like to stay with 03-05 style or to upgrade to 06 style. If anyone can shed some light what the actual difference in parts is - it would be awesome.
Looks like fenders are the same, hood is the same, headlights are the same. Bumper seems to be different. Anything else besides the bumper and fog lights?

Rudeney

The bumper, lower grille, and fog lights will all depend on year, model, options and country. Are you in the USA? (Please update for forum user's profile to include your exact model,.year and country). If so, then all V8's came with the AMG-styled sport appearance package, but if it is an actual AMG, then it has a different bumper. The V6 had an option for the sport appearance package, but it's not the same as the V8's. And like you have found, they made some changes over the years to the base V6 bumper styling.

HETPE3B

Yes, I'm in US. I forgot to mention that I'm talking about CLK 500, so yes, it's a V8. Based on your information there were no changes in the front end for V8's with AMG appearance pack for 03-05 and 06-09 styles, but only for V6s bumpers and fog lights. So that means it pretty much doesn't matter what would be the year for the donor vehicle I will be getting the parts from. That sounds good, like I have more model years variety in search of the donor car. Thank you!

Rudeney

One thing that I think did change along the way is the number of fins on the grille. The earlier models used a 4-fin style, and later they went with a 3-fin style. But other than the number of fins, it's the same fitament.

HETPE3B

Is the wiring for Halogen and Xenon headlights is the same? If yes - does the light control module (if there is one in W209) needs to be recoded to accomodate different type? Mine are halogens, but I just scratching my head looking for the donor vehicle if I need to look specifically for halogen headlights or I can purchase donor w209 regardless of the headlight type (obviously I will source necessary parts from donor vehicle if needed)?

Rudeney

The main wiring connector is the same, but HIDs also have a connection for the auto-leveling feature. And later models with the "steerable" HID lights will have another input for that feature. These are not necessary for the lights themselves. Without the these connections, you just won't have those features.

The front SAM must be reprogrammed when switching between factory halogen and HID headlights.

HETPE3B

If someone is interested - my project