Wiring harness should work. It depends on which obd2 you have. There was two versions of obd2. What year car what year motors?
The vtec solenoid will work.
As for the ecu, idealy you'll want the jdm one cause it has several sensors deleted, so your usdm ecu might throw codes and have some issues related to limp mode. Also, if your jdm b18c isbthe type r version you'll want the jdm type r ecu for sure. The usdm gsr one will run like crap and cause damage.