For what its worth check out the build thread of my 83 Tbird.
http://vb.foureyedpride.com/showthre...83-Tbird-build

I converted mine to a 5.0 and used a stock 90 mustang harness then bought a plug and play MicroSquirt kit from EFI Source for under $500 shipped to my door. Super simple to use and tons of features. Rest of my conversion is just OEM take off parts that are easy to find.