First, let me apologize about the sorry shape of my engine bay. I know it looks horrid, and this spring it's going to get fixed. Just too much snow and crap around here for me too keep it clean.
And also, I'm writing this assuming this is your first SHO. I'm pretty new to the SHO world, and thanks to the help of many SHOForum members, I have learned a lot!
Here's the engine bay
Labeled the major parts that need to be checked.
This is the Idle Air Bypass, and the vacuum hose.
Here is the cleaning procedure.
http://www.shotimes.com/php-bin/modules.php?op=modload&name=News&file=article&mode=thread&order=0&thold=0&sid=82
This is the vacuum controller for the secondary butterflies on the intake. If this isn't working properly (has a hole in it, loose hose, ect), the secondaries stick open all the time, causing a lot of issues below 4000RPM. Search the forums, there are some really good ideas on there on how to troubleshoot it.
Also, pull the Mass Air Flow (MAF) sensor, blast that with electrical contact cleaner, same with the throttle position sensor.