You could swap the 327 heads for some later, smog heads with big chambers and lower the CR to stand more boost.
I had a turbo 2.3 Mustang that had 9.0 comp. and 8# boost, when the limiter valve was disconnected it made 11#, ran like a raped ape for a year or so till a cold weather startup tore the cam out of it. Bummer!