sometimes, depending on the engine:)
An eight feet bed of a 2009 dodge will fit a 2006 dodge 2500 with a little moderation.
Yes.
It will fit in any 2500 or 3500 Ram. If it is a different version of the Cummins it will take a lot of modifications to make it work.
Yes.
Yes
No.
No it will not fit. You would have to use the 2006 fenders, grille and Headlight assembly to fit the bumper.
Yes.
No.
Yes
Yes
1500, no. 2500/3500, yes.