Were you pleased with the result? Did you place all the injectors above the blower or did you put some above and some in the intake runners? Did you build your own system using rails only or did you purchase a spacer with rails attached? Which electronics did you use? Probably many more questions coming up?

I did it....except without the blower. Couldn't afford both.

https://www.youtube.com/watch?v=-AXRHXSV5Jc

With a blower you want 8 injectors above, and 8 below the blower port injected. Rich at FastManefi is a great source of info and has built many of these. I can tell you a bug catcher is touchy to drive on the street. I had to have two programs, one for driving, one for racing. Now a days, they have a progressive style available.

Me, I would use Holley EFI, and rails, you can get almost anywhere. Also the conversion above the hat is available in a few different forms. BDS has a real nice injector hat efi spacer, and there are tons of others as well...

I tuned a Pro Street car (more like a Pro Fairgrounds car) that had a blower with a hat with sixteen injectors in the hat. It was all looks and not much performance since the combination was way too squirrly to drive. But we did get it to start and idle so he could drive it around at the car shows. The guy had a ton of money in that car and it was barely useable.

The big problem with using a hat as your throttle body is that hats aren't designed to be very precise. Throttle bodies are machined to very precise dimensions so you can control the airflow and maintain a steady idle. Hats are just cobbled together drag race parts. When you use a drag race hat as a throttle body you have a very difficult time controlling the idle speed. It ends up being kind of a joke of a system for a street car, works okay on a drag race car with a high stall converter.

I converted one to efi. It was an enderle hat. The guy bought the car site unseen over the internet. Had no idea it was a mechanical alcohol car.
Made it appear to be true mechanical with injectors inside the hat. Used the steel mechanical injector lines as the feed tubes to the iac motor. I found out that in order to make it drivable as a street car with a decent idle speed, i needed to block off the two outer most throttle blades. Turned out to work pretty nice. A whole lot of fab work to do. Even more than I am used to, and I build damn near everything.
The blades are to darn big to have controllable idle below 1300 rpm as originally built. If you close the blades enough to get a real world idle speed, they flex, suck shut, and bind. My cure was to plate off the outer blades inside the hat. This allows the outer appearance to to maintain the look, yet still have a single blade to deal with for real world drivability. I found out after the fact, that the bds kit does exactly the same thing with blocking the blades.
It’s been years since I did it. I believe the blades were around 4” each, so even one is plenty for a street performance style engine.

Joe Blow out of Australia make a real nice billet injector hat with built in EFI, not cheap but with concealled wiring & fuel line is a very trick piece.

One of the long time drag week guys had a hat with progressive butterflies and EFI. He has since gone turbo but he ran this combo for a long time.

You can see the progressive butterflies here.

I remember seeing a hat spacer that had the injectors in it. Was a nice setup. Check on Good Vibrations racing website.