dammit why didn't you SEARCH
anyways the SH header is longer than the base header (the B pipe/flex pipe is longer), so you would have to shorten that section of SH header in order to fit it to a base.
in all seriousness, searching better would have given you the answer.
also, if you are planning on doing a lot to your car / have high horsepower goals, dc headers probably would not be the best choice.