My throttle shaft is leaking, but it seems to come and go; not that bad yet. I had a guide pin stick on a 93 I got one time. I called PDR, talked to Harry (not Piers), and he kind of guided me (pun intended) through how to get it unstuck, and if that didnt work, try this, etc. I ended up taking the top section off, and using a flat screwdriver to pop the guide pin loose. Then took some PB Blaster, and sprayed it liberally, put some synthetic grease on the pin itself, and moved it back and forth until it would move freely. Put it back on the truck, and it ran good ever after. I didnt remove the AFC housing to do any more adjusting or tweaking, though.
The 93 W350 I had is leaking, too, but I havent been able to get ahold of the guy about it, either. Think his pump needs a complete seal kit by now.
Pastor-
If you need someone to do some R&D; I'll be a guinea pig. Just PM or email me, and let me know.
Daniel