Im sure hes got the suspention, chassis and engine work done, judging from the work Ive seen him come out with..
Would think so right.. Guess hes got a thing for lighten cars not weighing them down lol...
Get some springs that can stand up to around 5000-8000lbs if so much..A more accurate weight of the final product would be helpful here.
As for engine, Im sure you ahve something that can stand up to the heat/wear/tear of revving at 2500-3000 rpm and put down some serious torque to pull that beast. Try to get it with a stong gearbox so as not to put any strain on the tranny..
Try the tech forums/nissan forums for some ideas on engines that will fit your application and suspention/chassis upgrades to accomodate the added weight..