ecm pin outs

does anyone know if all the pin outs on the 1999 to 2005 ecms are the same for example i am looking for a wiring warness do dyno on a engine dyno i have a 8.1 motor and called around junk yards and found a 4.8 in a truck 1999 i am assuming they have the same plugs on the ecm so i could use it a make a dyno harness just like to know befor i drive 1hr there cut it out and find out when i get home there not the same

thanks

Watch out for the fuel injector plugs, They are different on all the trucks,