anything can be done dude, you just really need to watch every step, test the strength and reliability of each part, and work the weakest link. I'd love to do it, but for me, there really ARE budget constraints
forgies a must (most of this has been established), rods -> GT-R ones are prolly a cheaper option?; cam timing, hi flow turbo, and basic support systems like exhaust, FMIC, fuel supply etc.
It's gonna be tight-ish, but possible.
A price hunt needs to be done, i'd get one started now, but boy am i buggered