do i need to drill holes in my tank just to have a sump?

Rigos right.If your tanks not drilled,just get yourself a HOB overflow.A lot of pre-built sumps come with the HOB overflow.
Pro-Clear makes one thats rated for like a 125.It comes with the overflow box and supply hose.It also comes with 5 or 6 feet of clear vinyl tubing to use on the return.All you'd need is a good pump and some stainless hose clamps.
BTW,that is what im running on my 55.
Like thay said you can just add a HOB but you have a better chance of a overflow of the tank if you loose siphon or dont have it set up just right. If you want it drilled you can do it your self or have a pro do it for around 25.00 per hole. If you do decide to drill make sure its not tempered you can not drill tempered glass it will shater. I have drilled three tanks now the first was tempered and busted then I drilled a 10 gal a 20 gal and they turned out just fine. Personally I'm a fan of the drilled over the HOB but alot of people use them very sucsesfully.
im using one right now on my 36 its pretty nice, however i am having problems with the syphone. for some reason it keeps losing it slowly and i have to re syphon it like once a week. i dont get it but when it gets slow it cant keep up with my return. it really sucks when my return sucks air at 3am and wakes me up haha but all around its pretty sweet, still not as good as drilled and hard piped in though. and if your going to drill the tank you can always do another hole for a closed loop for current with an external pump. that is for sure the way to go for current. i was really wanting to do it on my 80 but i got impatient and wanted to set it up in a hurry. maybe next time.
Silvia s13redline.... rb26dett's kick ass right? You know why they kick the sr20det's ass... because they breath better (twin turbos with 3 inch exaust instead of single turbo with 2 inch exaust)..... Anyways i'm going somewhere with this, get some bigger tubing for you refuge. That way the waterflow can keep up with your pump (AKA ur turbo being able to push out all that exaust). I know only you will get the analagie. lol
Silvia s13redline.... maybe you have a boost leak....... do you have stainless steel hose clamps on all your tubing fittings? (again another import-dork analagie) BTW cant wait till you get up here this weekend! Mothers watch your daughters, Hawks and Redline are going to be out on the prowl!