Being a Car Guy i am always looking for stuff like this so i know others are too so here it is.
This is a Part Number Identification for Most Cars out there today
It Has Info about how to find and identify the part numbers on Engines Transmissions Fron and Rear Axle's and Decoding certification Plates and Option Codes
I Hope to get the Complete Interchange Book put into PDF someday but its about 15,000 Pages so thatll take some time.
but here is what i have so far hope it Helps some of you
P.S. I will be Keeping this on HD even after i seed it for a while so if the torrent dies just Ask and ill get ya a copy
its only a lil less than 5 mb si its no biggie to send real quick