The b16b is like 4000 or so and that is cheaper then the ITR, yes. The reason why i think the ctr is a waste is because you can raise hp like crazy, but tq isn't so easy to come by. So, the 22 lbs more the ITR has over the CTR, i think its worth the ~1200-1500 more for the ITR. ITR's can be had for 4650 (96-97) and ~5500 (98-00). The difference between the 96-97 and 98-00 is: 96-97 - FD is 4.40 and has a 4-2-1 header. 98-00 - FD is 4.785 and has 4-1 header.
ctr = 185hp 118tq
itr = 195hp 130tq
Yes, only 10 more hp, but tq is what moves a car.
For NA, get the ITR and for boost (turbo) go anything but ITR or CTR.
Yes, a complete swap should have the engine, tranny, ecu, wiring, axles, mounts (oem mounts) and linkages.
You need to use Teg tranny and side engine mount and a 99-00 Civic Si Rear mount to mount a b-series into your car. The shift linkage can just be one from a b16a2 (99-00si) or you might be able to use the ctr/itr one, i am not 100% sure.