I have no idea if the head have ever been flowed and I wasn't provided any flow information from the previous owner. I'll ask him. How do you do a hot valve lash without having inconsistencies in the settings as the valve train cools down?
You lash em fast. When you do it over and over you’ll get to the point where you can do it in no time at all. The engine will retain heat for a long enough time to do one side without it being too far off.