[quote=chic]Anyone upgrade to a teak cockpit grate on an older MkII?  I want to do this and looking for ideas and suppliers.

chic lasser
Spendin Time #1474. 1995 Mk II[/quote]

Chic -
  Several C36ers have had them built  (or have built them ourselves) for Mk1s,  I doubt there would be much of a conceptual difference, just the measures (which you'll need to dial in carefully no matter that).  See this thread:
www.catalina36.org/forum/general-discussion/cockpit-wood-floors. 
which has some pictures as well as some links to several builders.
   I fabricated ours from scratch, but I had guidance from a nice video instruction I purchased from  www.theyachtshop.biz/ , which includes the details of a router jig that made the job much easier and more accurate.  That shop also will make them for you.

Chic, I have purchased a few items from these guys: http://www.thaiteak-marine.com/  They have some templates for a few boats, but can customize it as well.  If there were multiple owners who wanted to do it, they would probably offer it as a standard item.  Prices are reasonable.