Hi,
I am replacing a 36x36 shower pan with a 36x42 pan. Do they make the pre-made larger pan with the offset drainage hole so I can drop it straight onto the existing drain pipe, or do I have to either move the drain pipe using elbows or whatever? Would it be better to just pour the new pan?

Thanks.

Warren (new to this, as if you couldn't tell)

If you Google "premade shower pans" you will find a lot of hits. Center and side drain.
Here is one source: Tile Ready Shower Pans

Assuming your 36 x 36 drain is in the center, no way are you going to find a ready made one with the drain offset 6".
I think it's easier to move the plumbing than it is to pour a pan.