I see 2 part numbers for the same gawdamn thing.

What are you driving? It looks like the same part for different years. looks like the AM600 is only good for 03, atleast thats what it looks like on infinitipartsonline.com

2003 sedan

AM600 = G35 1/2002 - 8/2002 for BODY ELECTRICAL > WINDSHIELD WIPER > LINK ASSY-CONNECTING,NO 1

AL500 = G35 8/2006 - Present for BODY ELECTRICAL > WINDSHIELD WIPER > LINK ASSY-CONNECTING,NO 1
G35 8/2005 - 8/2006 for BODY ELECTRICAL > WINDSHIELD WIPER > LINK ASSY-CONNECTING,NO 1
G35 8/2004 - 8/2005 for BODY ELECTRICAL > WINDSHIELD WIPER > LINK ASSY-CONNECTING,NO 1
G35 8/2002 - 6/2003 for BODY ELECTRICAL > WINDSHIELD WIPER > LINK ASSY-CONNECTING,NO 1
G35 6/2003 - 10/2003 for BODY ELECTRICAL > WINDSHIELD WIPER > LINK ASSY-CONNECTING,NO 1
G35 10/2003 - 8/2004 for BODY ELECTRICAL > WINDSHIELD WIPER > LINK ASSY-CONNECTING,NO 1

Most likely they're Identical parts.

If thats the case it looks like you can use both. Again atleast according to this site.

http://www.infinitipartsonline.com/o...iti/28841al500

http://www.infinitipartsonline.com/o...iti/28841am600

Would it be different it is one was for the coupe and the other sedan?