[supereal]

When in doubt regarding valve to head clearance, you can use the "clay" method that was common years ago. You place common modeling clay in the valve areas of the head, then install the head using the gasket. Don't tighten the head nuts beyond finger tight, then turn the crankshaft at least one full revolution. When you remove the heads you will get an impression showing any interference between the valve and the combustion chamber. That is an old "shade tree mechanic trick.