hi i've got a few questions for 05 and 03 crown vic p71's

ok so i have a 03 & 05 crown vic p71's. i'm curious to know what parts will fit from the 05 to the 03? will the air box from the 05 to the 03? what parts are interchangeable? and what parts typically go out on the vics so i can have spares before i scrape the 05 car out??? any insight would greatly be appreciated thanks so much