I'm in the process of converting my 2004 XJR to an X358 (plus a few other updates) and am a few weeks out from painting the new panels and bumpers.

Mirrors with integrated side repeaters were looking like Ł180 per side plus required an Auto Electrician at Ł120 (!) per hour to wire up. As a result, I looked into other options.

I didn't fancy cutting into the wings so decided to mount them in the plastic wing vent finishers. These are easier to cut and have the advantage of allowing me to keep the wiring in exactly the same position as they are on the X350.

I measured up a few repeaters and decided on some from the L322 Range Rover as they're small enough to fit on the wing at 46mm diameter.

Here's some pictures of making a few trial cuts with a Dremel on a curved piece of Tupperware which didn't survive a hot dishwasher cycle before cutting into the wings and mounting:


Traced template


Cutting the trial hole

It fits! Also fairly flush despite the curve


Transferring the template to the wing. This is positioned at the same height as the existing side repeater on the x350 to maintain the line from the reflectors on the front and rear bumpers


And here's the cut!


Again on the rear - you can use the somewhat conveniently placed grid on the rear as a guide


And they're clipped in securely!

Ł15 total cost and I think they look pretty good! Whole process took around 2 hours including practicing with the Dremel

 

I had been contemplating mounting the OEM X358 vents to my 04 X350, but couldnt land on the best way to mount them. Ended up purchasing aftermarket WALD style vents which I am very pleased with. Out of curiosity how are you mounting these- through the side marker opening?

 

I've got the X358 wings and kit (minus the mirrors!) ready to go on so these are mounted to the new wings as shown below.


Here's the wings with the vent unclipped. There's an existing cavity at the top which you could use for running cables through, although in my case the side repeaters are bit too deep so a hole needs to be cut above the lower clip points.



Here it is on the panel, although not fully clipped in.


Here's the positioning on the old panel - I've kept it in the same place as the current amber indicator as the wiring exits here so it's easiest to connect in this position without modifying it. It could be higher / lower depending on your preference but you'd either have a bit more slack or need to extend the wiring further down as it feeds from above.

 

Looks sweet! I like how it came together with your custom side indicator. Thanks for the pictures, that puts it into perspective as I didn't realize you were going to install the X358 panels as well. Never saw the panel with the vent removed, that is helpful.

Update us on your progress when you get a chance, there are a number of members that end up doing some X358 updates to their X350 and this would be a nice thread to reference.