If you feel carefully on a car that is not equipped, you can feel the mounting hole on the flat metal plate, into which this protective cage mount would fit.
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And the pin-out at the seat harness connector suggest I should connect the lamp between pins 4 and 18.
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Sounds like a weekend job!
Simple enough sounding modification.
Went up to the local scrappie, and got two bulb cages, so that nothing can accidentally fall on the bulbs. (Hard to get out from under the seats, since these are fitted to the posh leather electrical seats, and so there is no power to raise the seats up and allow easy access to the bulb holders. Oh, yes, wet carpet and broken glass adds to the entertainment at this point!)
Already had the bulb holders, from previous modifications.
Expected to pop out the seats, check the wiring, and (if lucky) patch the connector to provide the wiring to pins 4 and 18.
Stage 1, pop out the seats; easy job, four nuts from under the car, and one clip for the captive end of the seatbelt.
Stage 2, lift out seat. Check angle of recline, lower the headrest, and it should come out OK. Beware the bolts sticking out the base, which could damage the door seal.
Stage 3, turn over seat (preferably on a protective cover, so you don't get concrete rash on the leather) and realise that the document holder (drawer mounted underneath the front seats) obscures one of the two mounting holes (on both sides), and that the very wonderful and special connector (that allows you to drop the seat down on its bolts, and miraculously makes all of the electrical connections required) is so unusual, I've never seen pins like it, let alone have any in stock.
So, stage 4, is not simply patch in a wiring harness and fitting the bulbs to the cages, but involves quite a bit more.
Mechanical was drilling an additional hole so that the cage fits beside the document holder.
Electrical was similarly simple; run the wires across from the bulb to the connector area, allowing slack for the movement of the seat (back-front and up-down). I put enough spare wire to allow a chocolate block connector that can be pulled out from under the seat, and spliced the wires on the car side into the car harness lines leading to pins 4 and 18, and the other side into the new under-seat wires for the bulbs. If I need to remove the seat again, then I can undo the connector, and the rest is as normal.
Stage 5 is simple; drop seat back into car, putting bolts into holes in the floor. If it doesn't lie flat, check that one rail has not moved whilst the seat was out (easiest to pull the adjustment level, and the seat drops back to flat immediately). Fit and tighten nuts, replace two covers, clip captive end back into seat, and the seat is complete.
And repeat for the driver's seat.
The job in total must have taken an hour and a half, almost all on the first seat, working out what to do, where to find the right size drills, etc. The second seat took less than 20 mins, including extending the wires from the bulb-holders where they had been cut off short.
So the bulbs work OK, and exactly like the front foot-well lights, and provide light to the rear foot-wells, but the document holder casts a shadow.
But now I know how to take out the document holders, I might go back to the scrappie, and find out what the difference is for the lamp compatible holders.
Or accept that the luxury item I have fitted works well enough, and get on with tasks that really affect the operation of the car.
