So I thought I would bring this up because I've seen a lot of people looking for upgrades for their 6.9/7.3 IDI and not knowing where to start or where to turn to.
Also most people who have an IDI truck don't have a lot of money to spend on modify there engine, so FREE AND CHEAP mods are key.
So those of us that know these mods should share our info here for others to have...
I found this site to be EXTREMELY Helpful for me when I started messing w/ my old IDI Truck it has a lot of free and cheap mod articles:
Ziggster's page
Also I found this site today, they seem to offer some good parts for IDI engines:
Diesel Performance Specialists, Inc. - The Diesel Performance Specialists