hi guys

Im new to all this tuning stuff im doing a 5.3 swap on my 1988 Caprice, i got a 411 pcm but i found a p59 at the junkyard out of a 2005 2500 Express van DBC 6.0l an 4l80 the pcm has a OsID :12592618 but theres no XDF's for it but from what i been reading is that the 12587603 OS bin is a universal OS for the p59 an i can flash mine to that ..... is this right ? just wanted to ask before i flash it an brick it ..... also is the 12587603 have flex fuel enabled?