not to sound like a tard or anything...

The 4v head swap will be wayyyy expensive. FI would actually probably be cheaper. Anotherm good idea would be to build it from the bottom up(meaning suspension first). Just an idea.

Sorry, to break it to you, but saleens had the same 2V heads. Cheap centri boost or spray, with suspension and nice wheels/tires

Alot of guys have made it into the 12's with full exhaust, gears, u/d pullies, tubular k-member, suspension and slicks. You don't need to make a ton of power to get into the 12's with these cars, just need to get the power you have to the ground efficiently.

My old 00 gt had 3.73's, catted h pipe, mac catback, bbk cold air kit, rpm intake plenum and bbk throttle body. It was lowered on bbk springs and I ran heavy 17x9 chrome cobra wheels at all 4 corners. WIth MT drag radials the car ran 13.1 at 104. I didnt have a tuner or tune on the car. With a tune it shoulda went 12's I feel. So you said you are getting long tubes and 4.10's. Thats the right step. The stock springs wouldnt be bad if you want to run 12's. Probably some strange adjustable shocks and struts would help out. Also get some upper and lower control arms, sub frame connectors as well. Your going to need some good drag radials or slicks. And as far as the motor, intake plenum, t.b., cold air kit such as a JLT, under drive pullies, and a set of cams. I am not sure who has some good cams as a lot of people used to run the VT stage 1's or 2's. With those mods and a good tune and some good driving it should run mid to high twelves no problem