I live in Arizona at just under 5000' altitude. My engine build is for high performance street and I am trying to achieve a quench motor design with maximum power.
Looking for some help here BEFORE I have any machine work done on my block.
I have a 1968 440HP block that is standard bore at the moment. I have the 915 heads, the pistons (TRW 10:1 @ +.040), roller rockers, Eddy Performer 440, 870 cfm Holley Street Avenger. 4 speed with 3:54 Dana.

Here is what I am considering for my build:
Bore .040", machine to zero deck, 915 heads with 2.14/1.81 valves, 74 cc chambers, stock forged crank, forged flat top pistons, .039" felpro gaskets, leaning towards the Hughes 3237 camshaft with 232/237 duration @ .050, .576/.584 lift, 110 LSA with 1.6 roller rockers.

Premium gasoline is 91 octane here so my questions are:
What cylinder pressure should I be shooting for?
With valve reliefs CR should be 11.6 is this too much?
What modifications or changes to my plan would you suggest to achieve my goals?

Thanks in advance. I really want this to be right and altitude density is an area I don't know a lot about.