ok um kinda lost.....some threads say that the lt4 intake part number is 12550631
some threads are saying 12550630..

mine is 12550631 s the the lt4 intake minifold

 

My guess would be Factory and Kit, but no idea. Lots of store hits on 12550630 from Google, and lots of forums hits on 12550631. So I'm not sure what to say heh

EDIT: lol I see Capricemgr is his same friendly self on other forums Also, your answer:
http://web.camaross.com/forums/showthread.php?t=610253

 

1255031 is the p/n for production LT4 intake and 12550630 is for the GMPP LT4 intake