I will soon be replacing glow plugs & UVC harnesses and have read here in various posts that the valve cover gaskets are re-usable... also that they are made of hard plastic. Should they be set in some sort of gasket sealant to prevent oil leaks? I'd really like to have everything I need at hand to complete the job in one shot so if there's some "special" sealant I'll need I'd like to get it before I start.

BTW, the info. here has been a great help. God bless the net...

 

Yes the gaskets are reuseable and as long as they are not damaged or burned then no sealant is needed. You should be good to go!