Well, it's not the engine that's in question, it's the head.
The MOWOG 8 port casting is a race part intended for the A-block and if I'm not mistaken, was granted homologation status with FIA for use in Minis, but was never sold in a car, nor even attached to an engine which came from the factory.
Seeing as I have NOT done an engine swap, it's my reading of the rule that the restriction regarding port configuration in production, the overarching rule category in which GT falls into, prevails.
Now maybe I'm letting the rules have too much influence over my otherwise contrarian existence, and I'll drop an e-mail tonight to the rules folks, but I'm thinking that this is a no-go.
I want to eventually DO an engine swap, and I'll be looking at the MG Rover K-series engine with DOHC's, which, as you point out, is clearly legal in GT. In fact, I think a solid argument could be made for a Coventry Climax engine in this - Jaguar bought Coventry in the early '60's, and they merged with BMC a little later.
There is potential for some interesting options in this thing, and while I'll check out all of those options, for the time being, I'm content to see what this Formula 2 spec A series will pump out.
And Stainless, the first round's on me.