Removing footwell carpet - problem

[notsofast]

So I've finally got round to trying to lift up the footwell carpets in my old van, to see what problems with moisture/corrosion might be lurking underneath, and I've got a bit stuck.  The carpet fits under the seat rails so I've followed the instructions in Haynes for removing the seat, but I can't work out how to remove one torx screw that secures the rail at the front of the seat, beside the handbrake. Haynes says this can be removed by sliding the seat fully back, but when I do that, the seat still blocks access to the screw - see pic:
   
Any advice?

Also, at the front of the footwell, the carpet is secured under one of those plastic grommets (which just pull out), but also under a screw fixing that looks like it secures the pivot point for the throttle pedal - see pic here:
   
My question with this is: if I unscrew this, will some kind of nut or plate fall off on the engine bay side?

[Kieron G]

The drivers seat on our X plate M49 multispace goes back further than in your picture. Certainly far enough to access the bolt head, I just tried it

[notsofast]

Interesting.  I'm guessing Haynes was written for the Multispace version. The rearward movement of the van's seats is restricted so they don't hit the cargo area bulkhead.  I'm wondering if there's a special tool or trick for unscrewing that last screw.  Wouldn't make sense if it can't be undone at all.

Anyway, despite not really getting very far with this job, I have at least had a bit of a look under the carpet on the driver's side, though I could only see a part of the footwell:
           

There is a bit of corrosion there, but it's fairly light and not as bad as I feared. The worst bit is under the throttle pedal - presumably from years of wet boots.  (The orange peel effect beside the wires is some kind of sprayed sealant).

Hopefully if I can get the rest of the carpet up, there won't be any horrors lurking in the other areas.  Also if I can get the carpet out, it should be easier to see where the water is coming in from - it can't be from the heater matrix anymore as I disconnected it 10 months ago.

Btw, does anyone know if it's normal to have that circular black rubber bung in the floor, and if so, what's the purpose of it?  I was amazed to find that it just lifts out to reveal a hole in the floor, open to all the spray and crap flying up off the road.  In this pic the road beneath can be clearly seen through the hole:
   

[Kieron G]

Could you get just a Torx bit on the front seat bolt head with a small ring spanner on it? Preferably a ratchet spanner once cracked so you leave it in place while you undo it

[Zion]

Btw, does anyone know if it's normal to have that circular black rubber bung in the floor, and if so, what's the purpose of it?  I was amazed to find that it just lifts out to reveal a hole in the floor, open to all the spray and crap flying up off the road.  In this pic the road beneath can be clearly seen through the hole:

It's a drain bung, to let water out if the interior gets flooded. Make sure it's put back properly or water comes back the other way of course.

[notsofast]

Could you get just a Torx bit on the front seat bolt head with a small  ring spanner on it? Preferably a ratchet spanner once cracked so you leave it in place while you undo it

Good idea.  I'm not sure if I've got any torx bits currently, but that's easily remedied.  Anyway, I'll look into it.  Thanks.

[notsofast]

Btw, does anyone know if it's normal to have that circular black rubber bung in the floor, and if so, what's the purpose of it?  I was amazed to find that it just lifts out to reveal a hole in the floor, open to all the spray and crap flying up off the road.  In this pic the road beneath can be clearly seen through the hole:

It's a drain bung, to let water out if the interior gets flooded. Make sure it's put back properly or water comes back the other way of course.

Thanks. I did wonder if it might be something like that. (Though it can't be very effective at letting water out, as one time a couple of years ago I opened the door and found the footwell contained inches of water, lol).

[Zion]

Btw, does anyone know if it's normal to have that circular black rubber bung in the floor, and if so, what's the purpose of it?  I was amazed to find that it just lifts out to reveal a hole in the floor, open to all the spray and crap flying up off the road.  In this pic the road beneath can be clearly seen through the hole:

It's a drain bung, to let water out if the interior gets flooded. Make sure it's put back properly or water comes back the other way of course.

Thanks. I did wonder if it might be something like that. (Though it can't be very effective at letting water out, as one time a couple of years ago I opened the door and found the footwell contained inches of water, lol).

Yeah, it works much better at letting the water out when you lift the carpet and pull the bung out of the hole...

[notsofast]

Maybe the way they're supposed to work is you push them up from the underside and let water out that way?  Would be easier to access than removing trim etc. to get the carpet up.

[Zion]

How would you put them back in then...you're not getting this concept lol. They push in from above.

Also if you push up from below, the weight of the wet carpet will try to hold them down and stop or slow the water getting out.

Carpet up, bung out, water out, bung back in, carpet back down (after being dried out) - you wouldn't leave a sodden carpet in place anyway