no mate i didnt look under the bench, i'll have a look though. thinking about it if the rust I had to deal with got much worse then I suppose it would get through to that sort of area!
Just to give you an idea, if you whip a rear wheel off and look for the funny reverse star shape washer thingy where i explained and push around it with your thumb. That should give you an idea of how bad the situation might be. That said, the liners are a piece of piss to get out once the wheels are off!
I got a wire wheel head for my drill and went mad with it, fuel pipes, brake pipes, any bodywork that needed it, then after warming a couple of cans wax just emptied it everywhere, even the lip of the arch itself! Hopefully that should prevent any rot developing any time soon.
I was surprised by the arch liner to be honest, the car hadnt been driven in the wet for days but it was still wet through!

Next up, wheels need painting!