Manufacturers vs Privateers (LMP1)

[Mr Pink]

So I was thinking while lying in bed the other night.

It's generally regarded as more or less impossible for privateers to challenge manufacturers in the P1 class, which does of course make sense. In F1, however, which I consider to be the only other racing class with comperative techonlogy levels, "privateers" challenge for podiums on a regular basis (Force India for example).

I realize that the borders between manufacturers and privateers are a lot more blurred in F1, and that there is a much more well filled mid-field but I was still thinking. Why is it impossible in P1 but not in F1? Would say Force India or Williams be able to be competitive in the WEC if they put their minds to it?

This is of course a hypothetical question as I don't see anything like that happening but the subject interests me a lot and there's some very knowledgeable people on this board.