Something I thought I'd quickly mention that can be a trap for the unobservant, and even the factory as it's how my engine came from them, is the bolt holes and the gasket area in the head are machined so close you get left with a thin bridge of aluminium at each hole.

When YS assembled my engine, three of these bridges caught on the liner and two of them decided to lie between the liner and gasket (see the indentations), the third must have fallen away cleanly leaving two remaining intact. So to save any future trouble I just pushed the remaining two out with a bamboo skewer and now have one less thing to worry about.

Thin bridge

One that had bee dislodged at the factory

One indentation in the head gasket

A 2nd indentation