I recently bought my 405. I found that I had damp carpets in the nsf footwell. I removed the carpets to find them soaking wet, like a sponge.
On further investigation, I found that the aircon drain tube has never been plugged into the tunnel. It was tucked up behind the dash. When I released it, a lot of water came out.
It stuns me to think that this has been like it for six years! The previous owner hadn't noticed it because he had over mats and rubber mats on top. Also, the actual carpets are a bit rubberised under the pile.
I own a garage and know the lads very well at the local Dealers, where it was bought from and serviced at. They checked their records for me and its not had any work done to it in that area.
Landrover never cease to amaze me.

That's not good at all !

Must admit I always check foortwells on various cars ive had over the years for water ingress wether from air con drain issues, leaks through windscreens / sunroofs or dodgy heater matrix.

So much for vigilance during factory production then main dealer PDI / servicing work not to notice this.

Will you end up stripping the interior to dry out the carpets / insulation or just let it evaporate and dry naturally. I suppose a lot of work to remove everything and with the aluminium shell corrosion not as much of a concern as steel. Current
2016 MY L405 SDV8
2018 VW Golf GT EVO
2001 BMW Z3 2.2
Previous
2002 L322 TD6
2004 Mercedes R230 SL350
1994 993 Carrera
Range Rover P38 x3
Range Rover 3.9 EFI

I removed the carpets. Luckily, the front nearside, is just a small section. I found that the aircon drain tube had never been fitted into the transmission tunnel, to drain outside. It was folded up behind the dash.
I checked all of the wiring and control units. No water damage. All is good now.

Good result there, it's a good job you spotted and sorted it before any electrical issues were caused !

Nice looking R107 Merc by the way, I ran one about ten years ago 500 SL with about 280,000 miles. Been thinking of another they are a great car ! Current
2016 MY L405 SDV8
2018 VW Golf GT EVO
2001 BMW Z3 2.2
Previous
2002 L322 TD6
2004 Mercedes R230 SL350
1994 993 Carrera
Range Rover P38 x3
Range Rover 3.9 EFI

Yes, its a nice example. Only done 50,000 miles from new. One owner before me. Roof never been up, before I bought it. The guy always used a hardtop if needed. It’s a keeper. 👍