You won't hit > = 300rwhp with the stock turbo.
You can hit 260-290 rwhp... with a chip set, MAF and boost controller with the stock turbo running at 15 psi....... for a quick fix check out
www.gururacing.net they are said to have the best chips for a stock turbo on the market.
If you want to be in the 300 rwhp club you will still need the above mentioned but will need to move to a larger turbo, larger injectors.....Many options available..........
Check out lindsey racing, guru racing, speed force racing, huntley racing...............
The kit I am getting does not have a website yet unfortunately (Vitesse). Its a complete kit. So it may seem a little more up front, but as a total package its a great value!!! and the dyno numbers are just ...........how shall we say????? INSANE....
Will let you know how good it really is when I get it and install in a month or 2.
Good luck.
*** your other question about swapping parts over from the NA to the turbo incase you toast the turbo. Nothing much you can use from the NA engine so its not worth it.