What do I need to do to build a 1000hp turbo small block

At that power level, I would use all forged internals. Crank, rods, pistons and fasten everything with ARP bolts. Pay close attention to your piston ring end gap clearances. This won't be a "budget" build.
Having said all that, I'll also say that if this is going to be a street car, you'll have a hard time using much more than about 600 RWHP on the street unless you have all wheel drive. Even drag radials don't hook on the street very well above 600 HP. Maybe you can adjust the target HP goal down a bit and save some money.