Hi all, I need Left and Right inner rear lights for my A8 D3 4E 2010 as the current ones are really faded and will not polish up.

Welcome Michael,

Common problem, so most secondhand can be expected to be similar. 
Where have you tried so far? 
Kind regards,

Gareth. 

Hi Gareth, thanks for responding. I've tried the obvious...Audi Dealership, ridiculous price!! EBay, too many people trying to sell what i already have! So search not going very well at the moment. I've tried toothpaste and other supposed cures but to no avail, really need a solution as last 2 MOT's have pointed to the future problem I may encounter. Any help would be much appreciated.

Thanks Michael.

2 pointers which may help:-

Register your ‘want’ with on-line car breaker link sites such as Partsfinder - there are more. You will obviously need photos before committing to buy. 
Toothpaste!! Drastic measures are called for - mask around the lights and wet flat the lenses with 800 wet and dry paper, then do the same with 1200. Get ‘rubbing compound’ from your local factors or Halfords and vigorously rub this over the lenses to bring the shine back. Finally polish with car polish. 
You could try T Cut if you can’t get rubbing compound. 
Nothing to lose.

Kind regards,

Gareth. 

Thanks for the advice Gareth, I've already tried the T Cut method but no joy, I'll certainly try registering with Partsfinder and similar. I'll let you know if i'm successful.

Haven’t tried the wet flatting? 

Hi Gareth, I'll be trying the wet flatting today, nothing to lose and could save a load of money. Thanks again for the helpful advice.

Hi Gareth, only spent a couple of hours so far on the first one but before and after shows the result so far. I'll be working on both sides tomorrow providing the rain keeps off.

That looks good Michael. If you are happy with the result mark it as Solution.

Let’s see how Michael gets on with the other side first Cliff, before we mark this as solved. 
Kind regards,

Gareth. 

I'm with you Gareth, the jobs not done till the fat lady sings and unfortunately the rain is stopping play at the moment. I'm confident that from your advice I will have a really good result.

Weather forecast is good for tomorrow so hopefully i can complete the job, watch this space.