Hey all, I'm brand new to all this, and hoping not to display my ignorance by the questions I ask, but also not really wanting to brick too many pcms figuring it out myself.. First of all what XDF will I need to read my computer, and if I cant find the exact one, which one will work (see pcm/engine details below)? Is it the SERV# or HDW# on my pcm? Also, if I cant find the right XDF, will I have to download a bin and write that to my pcm or can I use the bin currently on my pcm? (the numbers have to match right?)

Here's the details on the engine/tranny/pcm
5.3 lm7 with matching factory pcm out of a 2004 1500
PCM Serv # 12586242 HDW#12583660
2002 4l60e out of a seperate donor truck

Plan is to put them all together in an 80s square body