+1 to what quik said. It will handle it... for awhile. The 4l60 is crap IMO. Even a fully built one will go with enough power. Just so you know I paid 1700 to have mine built. I could probably have got a 4l80 for less and had more. You can bout add 1500 to a turbo kit in just supporting mods. Then if you dont put it on yourself.... and tune....
I say go for it. Just be ready for a stupid bill in the end. For the money though and how much will will be able to squeeze from it later down the road its more than worth it.