Harness/PCM problems-2005 6.0 engine into an early build 2004 F250
My truck is an early build F250 SD 6.0 (built in Aug 2003). The engine blew, and I bought a 6.0 from a 2005 F350 drop-in complete with harness (but no PCM).
I was told "no problem we do these all the time-the 2005 harness will plug right in to the 2004 PCM".
I have installed the 2005 engine, and when I went to plug in the harness, I now realize the harness plugs on the PCM side are totally different. There also are quite a few different pins within engine-side plugs too, but those plugs are at least the same shape.
So, my questions:
What do I need to do to get the 2005 6.0 wired up in an early build 2004 truck? I have the 2005 harness, but not the 2005 PCM.
Should I use the 2004 harness on the 2005 engine, or get the 2005 PCM and use the 2005 harness on the 2005 engine?
If I change out to a 2005 PCM, will it work with the remainder of the 2004 wiring?
Also, does the FICM that came with the 2005 engine need to stay on the 2005 engine, or should I put the 2004 FICM on the 2005 engine?
Or am I totally screwed?
Thanks for any help on this! Snow's coming and I need to get this beast running.
Jim (feeling like even more of dumbass than usual)