Can anyone successfully answer this question? I searched and found a number of dead posts. I'm trying to do this right now. I'll post the solution as soon as I find it. So far I've found that the EGV328 or the 1978 5.7 4bbl egr flange works, but I haven't found a diaphragm that is small enough to clear the IAC. Has anyone done this?

 

I have done it, i had to fabricate a spacer to get it to work, i have since taken the car apart though and don't think i have any pics of it. What i did was grind down the edge of the "crown" area on the egr valve. My area of interference was with the valvecover though, not the IAC.