LBMs, stock intake, stock carb. Being a purist, this will always be my advise, "always use stock parts". For MANY MANY reasons, one being less BS in every way! IMO of course...
Definately something to be said for using factory parts. Pontiac engineers knew how to make reliable power in these cars. With few exceptions, most of the performance parts I've installed on my car were not the simple bolt on as advertised.