Yes. DG8TIM gave us all a photo of the ports and details of the HSC 2.3/2.5 engine. There are clearly a lot of changes to the 4 cyl head, and the centre inlet tracts on the I6 are grouped. The HSC intake won't be a bolt on, not even close, even if sectioned.
The option is still there to run an HSC 2.3 workalike HSC I6, but it would require a cut off log head, and a set of Argie ME, SP or perhaps 280 ZX exhast manifold. The intake and exhast off a 300 I6 could be extensivley cut and shut to suit, and Harrie, the66mustang, has a wonderful set up where the old I6 Log head gets an Aussie X-flow intake manifold. They guy is awesome!
There is another guy, HotRod here who has a 27T-bucket with Aussie Log six with log head, and a cross-flow EFI set up.
There is lots of work going into getting EFI on old 144-250 sixes.
To make it commerical, it'll need common parts, and the best bet is to rework the 4.9 EFI port injection system to fit the log head by welding six flanges. That way, theres little green field design work needed.Then get six tubes bent up to suit.
The conventional FSPP, Clifford and Hooker headers are cheap, and the port divider fixes most of the exhast problems. New cams from FSPP are designed to deal with the poor exhast ports of the 144-250 little six.
I've got my own personal project, but the details will have to wait until I get my project car running.