Damn you guys are getting way tooo technical. Just keep the build simple and learn of other ppl in the states or locally that has done it. There is no need to be creative when it comes to an engine build, unless you want to throw thousands of dollars out the window and look forward to dissapointment.
As for headers, 4-2-1 or 4-1 same deal. If the headers isnt designed well, then both will make poor power. Check out those cheap Tri-Y's. They are the best bang for buck headers out there. Works very well on most b20vtec