Lapping head to cylinders?

Can some one review me on how this is done?

When I did mine I used the granite surface plate at work and some 240 grit paper. did the head and barrel with a guid coat on each until both flat. worked a treat, so good that it didn't want to come apart at 100 miles. that was with an annealed copper gasket.

Need a flat hard surface. Granite surface plate is best. Cast iron machine tables like table saws and jointers are usually flat too. Or go to your local glass shop and get a slab of 1/2" thick float glass.

The head is easy, being aluminum. Cast iron however is slow going.

OK thanx will try that next time parts on bench, ugh. Good flat surface listing to keep in mind. I use 1" thick tempered glass from big broken dining table. Have big hunks left to try to cut size of sanding sheet if anyone interested. Left some at water jetter but he ain't got to it so far to see if scatters that thick or jet gets diverted spread out too much for the depth of hardness. On factory Trixie I use anneal copper and Hylomar to see it weeps-blow by prevented.

Used to lap mine on steel surface plates at work, but don't have that facility any more.
I now put grinding paste on the head & barrels & lap together. Use the same grinding paste as for lapping the valves in.
Lap crankcases together etc. same way.
Clean off with white spirit or parrafin.
I have never ever used any sealant on head gaskets.

OK Flo that's what I thought lapping meant, rubbing the actual mating surfaces together.