30 Gallon Reef

Well I am condsidering switching over my 30 gallon FW tank to Reef for the living room.  I have seen some very cool pendant lighting systems lately and was thinking about a DIY pendant light for the 30 gallon tank.  Tank Dimensions are 30X12X18.  If I hang the lights around 5 inches above the water surface do you think 4 24" 75W VHO lights would be sufficient for most corals, taking in consideration the 5 inches above water and 18 inch deep tank?  2 Actinics and 2 Aquasun is what I was thinking of using?

Or, I am also considering using a 175W MH with 2 75W VHO Actinics, one mounted on each side of the MH.  Would 1 MH be enough to cover the 30 inch width of the tank?

On another note, I would like to get the 30 Gallon tank drilled.  Does anyone know if any of the LFS will drill a glass tank for 2 bulkheads?

Thanks all.

Here is my small understanding of tanks.  I have heard (so don't quote me on this) that most tanks, unless otherwise specified, have tempered glass on the bottom of the tank.  If you try to drill tempered glass it will probably shatter into a billion little pieces.  So before you try and drill it, make sure it isn't tempered glass.  I have heard that some tanks will say on the bottom glass piece "tempered glass, do not drill".  I have never looked for it myself.  Hopefully someone else knows more about this than I do, but just be wary about drilling any old tank.

Thanks for the info guys.  IF this ever happens I will make sure to check the bottom of the tank and see what it says. 

Regarding the lighting, anyone use MH over a 30 gallon?