So I made these a while ago and don't really need them anymore, I have 5 sets of each...  Was going to keep em around to build headers and stuff but I really don't know if I'll use them.  This is an awesome piece for building custom headers or custom turbo manifolds!  With a 1/2 " thickness it makes for a nice flange!  
Here's what I have ( I apologize for the pictures, I took them with my blackberry...)
5 sets of flanges (1/2" thick and 1 3/4 holes)
5 sets of flanges (1/2" thick and 1 7/8 holes)
These were cut out on a water jet and are an exact match to ls1 heads.  If you're interested PM me.  
Price is $50 per pair shipped...  I could cut someone a deal if they're buying a few sets.  See my feedback for past dealings...  I gaurantee these to work great!