turbo my 5sfe, just a few questions...yes again Options

[celicaGT96]

ok...before anybody says anything i already searched and didnt quite find what Im looking for.
What i wanted to know is, how did the guys at burien toyota get their 5sfe motor to run at an everyday 14psi.
Im going to go through with turboing my 5sfe, buying parts slowly here and there,but Im reading on and on, and I wanted to know if theres any way to get a bigger turbo, even if it means upgrading internals.
What do I have to do to get the absolute most out of my 5sfe.
Also I dont want to swap to a 3sgte, and for pressure, and all others, did the bigger injectors really make a difference in power(which ones)??

[celicaGT96]

Well I know it nearly impossible but Im thinking 250-300whp.
Thats why Im asking if its possible with proper tuning, without blowing up my engine.
I know pressure got about 200whp, but did he do all that he could or is there different, better alternatives, to achieveing horsepower.
Thanks for your input though