Rough idle on cold mornings with occasional check engine light

[certified22]

I have 04 Tahoe z71 5.3 and on cold mornings I'll sometimes have rough idle sometimes get a misfire code some times just get check engine light solid rarely it flashes I get to lean banks 1 and 2 codes random misfire code MAF sensor code I've replaced the plugs the plug wires the fuel filter the air filter the MAF sensor all 4 o2 sensors and no change apparently there was an issue with the intake manifold gaskets being made in Canada and from everything I have read I believe that is my issue so I'm gonna replace,the intake gaskets but I'm looking for any info I can get like do I need any other gaskets or parts before I get started and should I go ahead and get the knock sensors too while its apart any info tips and pointers are welcome I'm pretty savvy with this shit but this is the newest motor I'm gonna have apart I've built several for different pickups and camaros older than 1990 lol so I got good idea on the basics of a completed rebuild but I still like other opinions thanks fellas