'67 Cuda 273 2bbl to 4bbl upgrade?

My 67 273 looked like it had shims but it was already apart when I bought the car. I know what compression they are advertised, but according to my measurements, and I think most will agree, advertised is on the high side. I used the 67 273 heads on my dirt cheap like new 318, here's some info:

2658920 (66-67 273 heads), closed chamber, milled .015, ported by me, hardened valve seats, Comp 901 springs, stock retainers/locks/valves, fresh valve job, mr gasket 1121g gaskets

318 heads measured 69cc while the 273 heads measured 62cc after milling (factory listed at 57cc)

Old (felpro) head gaskets are said to be .050 or more compressed New (mr gasket) head gaskets are advertised at .028 compressed Bore is 3.94 (.030 over stock), stock stroke of 3.31, effective dome volume 0 (not taking into account the volume of the valve reliefs, I'm not going to mess with it), deck clearance of .100 (measured).

I don't know how the 273 piston specs compare. It's rated at 8.8, my guess would be more like 8.0 but it's hard to say without knowing exactly what gaskets and the rest of the short block specs.

Just info, not really important for this post.