What's wrong with the highport head?
Also, I'm with you Ben, I'm just now getting to the point where I feel comfortable to WOT on my 9.5:1 DE+T, and I think I am detonating a little bit. Partial throttle is fine most of the time, but WOT always give me a little hick-up here and there and I don't like it. I will be playing with timing once I install the wideband and N60. It could also be fuel things (motivation to actually buy the wideband).
But a high compression turbo build sounds like a blast, if it were built/tuned right to handle it. Would definitely be a fun experiment.