glass drill bits

[e46er]

hey
so i moved my 120 G tank last weekend and am sick of crappy POS submersible return pumps so ive decided im going to buy another snapper hybrid pump for a return pump and it will run my 2 reactors as well im going to plumb in a bypass as well it case the flow thru the tank is too much
but now i need to drill my sump i dont really like the idea of running the inlet piping over the side of sump as start up with no water in the pipe is going to be hard on the pump

1) how low to the bottom of the sump do you think i can drill ??? it will be an 1 1/2 bulkhead so i was thinking bottom of hole 2" up from the bottom glass

2) an 1 1/2" bulkhead requires a 2 1/2" hole does anyone have a diamond tip glass hole saw bit lying around they would be willing to lend/rent out?? beer cash??