I have 2 Northstars a 2000 and a 2002. Both are VIN 9 (L37). The intake cams are the same but the exhaust cams have different numbers.

2000
LE 12560450
LI 12553013
RI 12553011
RE 12560448

2002
LE 12570338 G4
LI 12553013
RI 12553011
RE 12570337 G5

Is there a significance to the different exhaust cam numbers?

Wasn't there a "recall" or something done on those 2000+ models, because of a "harsh idle quality"? I vaguely remember something to that effect. Crazy old people... :suspect:

Yes, the cam profiles for the 2000 engine were modified slightly to achieve better idle quality due to customer complaints. Slightly less overlap. The 2002 cams are the running change camshafts for better idle.