i have an 02 4.8 with the 3.42's. The only mod i have is a shitty ravin single in/dual out muffler. I took it to the track in 80F heat with 85% humidity on a night when 02 z06's were running high 13's and my friends lightning that had run a 12.8 2 months before was running high 13's. i managed to nail 16.0's all night, trapping at almost 89mph (88.4), So i figure that if you get the pcm and that rearend, you should be pretty close to 14's.

 

you really save alot..
by installing it your self..
as far as numbers go..
it will vary but is possioble to do it for less than 800.
the cam will be your biggest purchase..
If you look real good in the sellers adds, you can usually find good deals on brand new parts..
thats what I did...