i ended up useing 5/8 fittings in the center of the block ,split that size in half for two large channels,"so there is no flow problem" and then went across the two chanels with 5 more smaller chanels. it kicks ass. so far best temp is 53F but i got to cool my water better @98F
http://www.geocities.com/jamestune_2...l?947305781960