just did a 411 pcm swap on my 2000 used a 2001 from my old truck same everything from the 2000 also has 01 motor. I used this pinout sheet from a 2001 blazer - http://www.ppepower.com/forum/viewtopic.php?t=10180 but noticed i got a fe extra wires a couple 12v reference a bunch of low reference gessing grounds ?and some 4wd wires ?and maybe a couple more ill hav to number witch are the extras,and only 1 extra from the 2000 pcm witch is a ignition positive voltage. i got the truck running but its rough, havnt tried moving it in gear.also got no fuel gauge it shows empty? still need to wire knock sensor. any help much appreciated. 2000 with 2001 pcm.hpt19-05-04 13-55-53.hpl