I plan on going the EFI route when I build one and will most likely have Westers Garage re-program the stock ECM. I am glad that someone is speaking highly of me for once (please someone tell the wife)
I do keep having dreams of TWM throttle bodies on the side of the Vortec 4200 with a custom aluminum valve-cover with fins and a high polish shine.

here is TWM's web site -
http://www.twminduction.com/ DIYEFI went the MS route which I find intriguing. I may go Autronic as a good friend is a dealer and I can get him to help with tuning issues.
Scott