Hello i see that you question has fallen on def ears. there are many reasons for that.
So will flame you for not searching the post better. truth is for some unfathomable reason there art any subsections in the technical section TO BETTER FILTER THE 10 BILLION POST THAT HAVE BEEN MADE.
So, to your answer;
1. 3.0 TT swap- everyone has done one and can tell you that it is complicated and will result in allot of blood letting.
you will then emberk on a long process of tuning then upgrading turbos and all accessories.
2. NOS Wet- Cheep in comparison. at some point you will blow something." i am trying this on my old motor for fun"
3. VQ35DE. One would think that the major shops would have jumped all over this. No one has
4. 4.8 V8 some have but an ugly motor to look at.
5. RB25/26 swap - more room but the length means you have to mod the hood- but the RB25 transmission is the same as VG3.0.
6. SR20DET hump back- 550hp power potential lots of room in the engine bay. folks will annoy you with snoby remarks about how they have 2 more cylinders then you. the motor is drift and time attack proven.
The dark Path:
7. US V8 LS SWAP- same or lighter then a VG30de. lotts of tuning info from local hotrod shops. and all 3.0tt owners will hate on you. although secretly they wish that they had done the same. FYI- Sicky motorsports is working on a swap. package.
. im a little stuck on c deciding between vq30de or vg30de i kno that they would fit bcuz the chevy guys put v8s in these trucks all the time and ive seen some people have rb's in these trucks. i know i might run into a problem with the wiring and probably the rear-end but i have time to play with. also im wondering if any of you guys or girls could help on the decision and any bulid tips if possibly. thank you guy in advance