I've been thinking about this modification for a long time now. I was never a fan of the stock mirror plinths for the Elige, they always looked a little bloated. The new ones on the V6 Exige S are much slimmer and more modern-looking. Before we begin I want to give credit to LotusCC for trying this out on his Elise and confirming the fitment.
Alright, let's get started. For starters you will want to order:
1 B138B4023F Plinth Mirror LH Lotus £5.91
1 B138B4024F Plinth Mirror RH Lotus £5.91
1 B138B4103F Cap Mirror Plinth LH Lotus £3.03
1 B138B4104F Cap Mirror Plinth RH Lotus £3.03
That's right, only £17.88 for all the parts. I ordered these from DeRoure and it took less than 2 weeks to get to me. They show up unpainted, I just sprayed them in black to match the rest of the trim.
The stock mirrors are attached to the door panel with three allen head screws. All three holes are covered with a black circular sticker, keep in mind you will need to roll down the window to access the lower screw. Be careful to not drop the screws into the door panel during this step, I did it on both sides...
Once the screws are out the mirror should pop right off. Now behind another sticker on the stock plinth is a single T20 screw. Remove this to free the mirror from the plinth.
Attach the new (and much lighter) plinth to your mirror assembly. The standard plinth only used one screw, but the new one allows for two. I highly suggest finding another screw and using both holes.
Attach the new mirror and plinth assembly to the door, just the same way you removed it. The three holes line up perfectly, once you have it bolted up tight you can attach the covers. Here is a shot showing the difference between the old and new mirrors:
Overall, it's a fairly simple and inexpensive modification. Again thanks to DeRoure for getting me the parts and member LotusCC for confirming fitment. I still have yet to drive with these installed but I don't expect any issues, it may even help my visibility!