That's a very good question, and exactly something that I'd be asking as well!

You see, I'm in the middle of a swap, from 2002 3.0 to 2005 4.8. Hell of a swap.
But basically I tried to keep parts as much separated as I could, but it's hard to keep track of everything.
So many parts are different, even if they look similar. For example the fuel pumps are different, the aux water pumps are different, even if both look exactly the same.
This is a crazy project lol.

Some things I still haven't figured out. For example #3 and #5 are the same, but why do they have different part numbers? What's different about them? Nothing