Ours is original and it is over the dinette - which makes sense because it's kinda in the center of the trailer so it shines the light everywhere. If boondocking without electric you may depend on that light for the basic necessities so you would want to maximize it's use. Ours is installed with a 1/4" copper line like the fridge and heater - I don't think anything else is "rated" for propane distribution - every one I've ever seen has copper line.
Here's a picture that shows where it is - the top of it is about 4-6" from the ceiling, but it has a heat shield to deflect the heat out. If yours is turquoise, it's a slightly different (newer) model, but the mounting height should be similar. I also think placement should be determined so you don't bump your head on it...
Shari