This may not be what you want to hear, but putting in an aftermarket TBI harness might be the quickest and easiest route for you. I read your build somewhere (I can't remember where right now), and you have put a ton of work into that thing. Since you have the TBI hardware already, check out
www.fuelinjectionconnection.com . Their harness is $245 shipped, and will plug into what you already have. It's cheaper than a painless harness, and you can just plug it right in. Your fuel system is already run, you already have the ECM and correct distributor, etc. You should be able to plug and play.