Noiceeeeeeeeeee!!!
This will be gr8 , but you will need some more things , the rb25de got 200hp i think , and it's more heavier than the sr20 , and wangan cars got over 650-700hp mostly, so if u want it n/a or turbo , ypu will need extensive work in the engine , transmission , suspension and brakes. You got yourself in a nice start , needs some work , but you are close to your goal, if u want those parts check out Mackay's website , he can sell to you gr8 parts for your project... Anyway , keep it up dude!, i'm stoked!
(oorp : Strato sold to you an RB25, not an RB26 lol)