Cylinder head cc

[LongBaz463BHP]

I need to get the CR down on my new build and it has been suggested that CC could by increased from 28 to 33. However that doesn't bring it down as far as I would like. What are your thoughts on decompression plates. I know that Neal has successfuly used them on his previous twin turbo, I would need a 1.5mm plate to bring mine down from 9.9 to 8.6
Thanks
Barrie