The only McLaren that was truly painted "Yquem" was the last F1 road car - #075. Unfortunately, you won't find many high res pics of that car, or really many photographs at all.
There are two other cars - Dan Kennedy's #038 was painted a similar color called "Kandy Orange" and there are plenty of photos of it floating around. The other F1 is the last car that Christies auctioned - #073, reportedly painted "Kandy Orange Metallic". There are a decent number of photos of it as well, but again it's not the "Yquem" car you appear to be looking for.
Here's one of the few shots you will find of #075:
>8^)
ER