You don't need a Haltech ECU for the IQ3s.
Racepak sell modules that translate between most aftermarket ECUs and the dash.
So they have modules for Motec, Autronic, AEM, Big Stuff, OEM Corvette ECUs, DFI, Haltech, MEFI, Pectel, FAST, XFI and some sort of generic CAN interface. Doesn't look like they do one for PowerFC at the moment. Worth speaking to them though because they are very pro-active if they see a marketing opportunity.
There are also two versions of the dash. A full logging version and another that just displays things. The one linked in this thread on modyourcar is the display only version. Either versions can be hooked up to any ECU that has an interface. Or you can run them without any ECU interface at all. Just don't have as much to display or log.
There is a guy called Mike Runge here in Australia who is stocking them. I'll try and pull his email off of my laptop if I can get it to work after running it over this afternoon with the Evo Bizarrely enough whilst pulling out the Autronic interface from my IQ3 setup to lend to a fellow IQ3 user whose interface had died and is entered in Targa West next weekend.