Where is stock needle at normal temp?

[grebus1]

I know this has been discussed before, but no one seems to have the definitive answer. Where is the stock temp gauge needle supposed to be when the engine is at normal temp? At the first mark or in the middle? Is there any literature (owner's manual, shop manual) that documents this? Mine used to read at the first mark but I had to replace the sender and now it reads half way. The sender came from LectricLimited and is supposed to be properly calibrated.

BTW, the gauge on my '99 Cadillac reads dead in the middle at normal temp.