I know you said ITB's, but just in case someone out there wants a view of a different group of options, I am posting a description of a Single TB Installation on my 1974 Porsche 911.
The basic EFI Kit came from Bitz Racing and consisted of the ECU, wiring harness, fuel Injectors (Ford 30#), Fuel Bars and misc bits.
I also obtained the following Used parts from eBay and Rennlist: a Porsche Single Throttle Body & a Set of (6) Porsche Intake Runners.
My old Fuel pump only produced about 6 psi and the EFI needs around 36 psi, so I bought a Fuel Pump from Summit Racing and some small supplies like fuel hose and filters, and an air intake system were purchased locally.
I did the Programming over a period of about 2 years working part time. In fairness, the default settings provided by BitzRacing worked great right out of the box. But each setting needed to be tweaked for my specific Porsche and environment. I was surprised when after hooking up all the parts, fuel lines and wiring, I reached through the driver's window to turn the key. I was expecting it to crank over and over and perhaps build oil pressure. Well, it did that and more! It rolled over 2-3 revs and fired up, then it idled smoothly at approx 950 rpm. I was all smiles!
I have been running this system for roughly 10 years and have not had a minute of trouble until a couple of months ago. To his credit Tony Bitz provided email support answering my endless questions with patience and knowledge! I ending up finding a fuse blown but had Tony go through the ECU just to be sure there were no problems in that expensive part. Thankfully he found no problems and returned it to me all for a small (IMO) fee of $50., which I thought was completely fair. I still have not found a reason for the 3a fuse to blow but I replaced it and the problem has not repeated itself.
The bottom photo shows the "Before" look with a pair of Weber 40IDA's. The top photo shows the Finished almost EFI Project on my 2.7L engine awaiting the Air Filter System, etc. #3 shows another view of the completed system. Enjoy!