If your going with piston zero decked most go .040" gasket for quench, I don't know if that's will give too much CR, maybe that's why the .050" suggestion.
273, he said he grabbed his calculation charts and calculated 10.5-1 up to 11.0 to 1 with the pistons I plan on using. No zero decking mentioned. That blew my mind. Literally. Was not expecting that at all.