.0020-.0022 on the rods and .0023-.0025 on the mains. Full groove mains and a HV pump. Pressure should top out at 80-85.
As long as you don’t run into detonation the cast piston will take quite a bit. To be safe, I’d follow RRR’s advice of 10.5:1 or even 10:1. That will help keep you out of trouble.
7k on solid lifters doesn’t require a whole bunch of spring. And the 273 rockers will take all of that and then some.