TorqStorm Supercharger build advice needed

Looks like we are going to shoot for 9:1 on the compression. So his head already has been shaved .030”. Rough numbers show that .090 off the head is usually around 9:1. Not sure if we should take another .060 off it or just take .060 off the block. Based on the shape of head chambers it looks like either will basically yield the same numbers. This is also assuming the use of a felpro head gasket. Let me know if I’m way off here please.
So 9:1 with 6-8psi of boost. Is this practical with 91 octane fuel or should we leave the head at .030 and not touch deck height?