Generation IV Internal Engine - 5.3 Swap Questions

Ive been exchanging texts with one of my friends that owns a shop (Audi Specific) about a motor he got laying around. But im a little lost on figuring out what motor it accually is. So heres what he tells me...

Iron Block 5.3
Out of a 07
243 cast heads

apparently its completely stock. never touched never opened up.

Also, it may or may not be a flex fuel/AFM motor, i really dont know how to tell if it is or isnt.

What my plan would Consist of is this,

Iron Block 5.3
243 heads that are currently on it
LS6 Intake Set up

BUT, even more questions come to mind when i get to the PCM/Harness...

i have the Harness out of my 01 Z28(A4) would i be able to run the prior stated 5.3 set up with this harness ?

It should be a lmg or ly5, depending on if it has flex fuel. You can run that harness and computer but you will have to buy the lingenfelter 58x to 24x reluctor box or change the reluctor ring on the crank.

doesnt seem to complicated... thanks for the help man