Clearance with dry vs wet clutches

I don't like words like "minimal". Mopowers, what was the actual measured preload? I ask because any amount of preload is that much closer to inversion. I think I'd rather have play than preload. I can't spend $100 extra on rebuilds then mill every piston as well. As long as the clutch pack isn't overly loose, then spacing under the piston won't result in the piston coming up out of the bore. I just don't like the idea of that clutch retainer ( l learned new words) flopping around.