first off id like to say welocme to SAU qld ;-)
mud is right i think after ya done the mods you will have a nice lil sleeper but i think you might be selling ya self a bit short when ya said 300hp , im runnin somthin very simler to you in my r33 . i got t04e on modifide hiflow manifold , 750cc injecters and running 35mm external gate thats been plumed right back to the bend ( for better flow ) and with a good tune and my safc2 dialed in right i got 400 rwhp
neway good luck with it
cheers ...... ;-)