Hi,
They have said on here to spray the head gasket with the sealer just as you are going to put the head on the engine, so the sealer is wet as you put the head on.
The head bolts need sealer too, but not the copper spray.
Below is info I wrote at a post about putting the head on a Cub engine, and showing the sealers. My post is part way down the page.
http://farmallcub.com/phpBB2/viewtopic. ... 3&p=807860
The Cub service manual shows the torque sequence for the head bolts.
Below is the page.
http://www.farmallcub.info/manuals/gss- ... 001-14.jpg