I just would never put a block back together without boiling it out.
I don't like pulling engines enough to do it multiple times.
Most machine shops will clean a block for well under 100 bucks if its fully stripped when you bring it in including all the freeze plugs, and all the threaded galley plugs for the oil galleys. An hour in the tank and your block is CLEAN!
Just me, I run em too hard not to feed them extra good...
Dave