I inquired about this a while back and DC said you had to use the top piece from one and the bottom from another,effectivly you'd have to buy two so I didn't look further.Maybe they added something to the line up,give em a call.
No No NO! The same header fits. 1pc or 2pc. The only thing you need to do is cut a notch out of the header where it meets the head. Right on the lower corner under the #1 cyl. Do a damn search cause I have seen numerous sites that state this. Do a search for the 92-95 civic EX/Si greddy turbo kit on a ZC. You will find it! There are even pics of where to cut.