Well yea, he knows you can use an obd2b harness, he said he doesn't want to do that though.
If the interior green harness is the same for obd2a and obd2b (i have no clue), just plug it all in?
The 98 ex obd2a engine harness is going to plug into the obd2a b16 ecu just fine, I'm just not sure about that green plug, sorry i can't help more.