Just to let anyone know who has easy access to an entire wire harness... the under dash wiring is actually pretty easy to get out if you have a little patience, and we've converted a CRX HF wiring to SI wiring in about 2 hours, the only thing is that you want to use a crx wiring harness for a crx and a HB harness for a HB... the only differences were the door harness which had to be cut off and also one connecter on the steering wheel which we didn't really care to figure out, since we had a crx SI one handy (we had a civic SI one first)

So, it really is a valid option to just swap harnesses if you have access to an SI and don't feel like cutting/splicing (although, like I told my friend, it's all electrons flowing through copper, either way works)