can someone give me advice on setting up a herbie overflow

[megs_clark]

Well yesterday the hole saws came, and this morning we drilled two holes on the back corner for the drain. We were going to drill two more holes for the return but it took a long time to drill the first two so we decided to stick with going over the top for the returns. Were pritty much going to go exactly as Marks diagram showes but will probably put in two returns? Havnt really decided. Right now im off to get some glass cut for the overflow, Getting more excited, thanks again for all the advice