1.) 345
2.) Yes, use the existing plate that the EGR bolts onto the intake with and fabricate your own solid gasket with some silicone to seal it. One of the easiest things I have done...
3.) Use one of your butt plugs... Hehe, j/k. NOt sure what you could use...
4.) No, they are tucked up too lcose to the frame rails. I think Nitrous is trying to get some LS1/OBS headers custom made by someone. Check his thread to see the progress on what has happened...
5.) It should be---on the driver's side towards the back where it heads down the backside of the motor...
6.) You can reuse it, but getting the tranny cooler lines to match up might be an issue (if your truck has tranny cooler lines)
7.) I would recommend getting an 02 PCM for the LQ9. The 99-00 PCMs had a slower processor and the 01-02 had a faster, better reading processor.

Since your truck has the cable TB, I would go ahead and put on a cable TB for the LQ9. The other details can be adjusted with the tune...