Gasket match lower intake??

if i port my lower intake (cobra, aftermarket) to the same size as my fel pro gasket, will i have to match the ports to the ports on the cylinder heads? i have GT-40 y303's and wasnt sure of port size. my but if i do one, will i HAVE to do the other?
 
If it is a stock Cobra intake, the ports should be the same size as the head's ports, so leave them alone. If you miss match ports, you will loose airflow. It's all right if the head port is larger than the intake port, but the heads and intake should match, the gasket size, so long as it is the same size or larger than the runner ports, is un-important.