'1967' 440/375 HP and 440/350 HP Comparison

Paul, a stupid question if you don't mind? Not trying to throw you off track.....but I think this kinda fits in.

You said the 375 HP 440 had 10:1 compression......and I am sure that's rated correctly. Does that mean they used the "Six Pack" piston or did they get the compression from the 67 only closed chamber heads with the "standard" 440 piston? Thank you drive through.

Oh and awesome info as usual.