John we've been using Cometics for years after encountering problems with dead softs and orings , My Buddy Hals BGF motor and Joshs both have them and Hals has 4 seasons ,They're laminate type gaskets similar to those even used on a lat of late model production stuff ,They(Cometic) have even made gaskets one off for us for special applications, kind of spendy but well worth the investment , I'm with the rest here re the Rot assy, go for the Steel,Forged,good rod & bolts etc delio and check out Summits (Dart) Iron rec port heads (smokin prices) It will all give you the confidence , I bought a couple of new Howards steel cranks a year or so back for a buck and a half each, ones still running in an 8.0 Alchy flat . Lots of good deals on rods and Pistons out there too ,if you just scout around ,let me know whats on your wish list we'll sick the kid on it ! Tommy
(re the "water" ,creat a positive shut off , it will be a non issue ,i'll explain)
(Cometic dealer )
http://www.cometic.com/gaskethome.aspx