Iowa....before buying FAST, Holley etc., check out FItech. Several guys on here are installing with good results and the system is very reasonably priced. Here is one install as an overview.
http://67-72chevytrucks.com/vboard/s...d.php?t=653268
I haven't done the math for carb vs factory efi cost on an LS. Is there that much savings? My personal preferance is the solid driveability of the fuel injection.