I stumbled upon that IAC while digging through Holley's site. It seemed to be a good fit so I grabbed it.

When I injected the TT440 so many years ago that NOS Y block was the cheapest so it went along for the ride. Also on that motor was an old Mallory 4309 regulator mounted on the rear valley wall of the block. It served admirably for a decade then sat unused for 7 years. I didn't trust the old diaphragm and and having trouble finding a replacement. Instead of forcing the issue I picked up an Aeroquip and stuck it on the back of the manifold. It should have no problem dealing with this relatively mild application.

The long feed lines look sketchy but allow a bit of freedom when it comes to servicing the system.