Thanks guys,
I went over to oldGMCtrucks site and it appears that the poly mount was the hot item in 2004 but for reasons unknown at this time the thread petered out. I've got a phone message and e-mail in to AD-Engineering and will post the findings if and when I obtain them. I had previously run across the topic of the poly mounts here also.
I would still appreciate more discussion on the clearance situation as described in the Shop Manual. This topic was discussed some over at Old GMCtruck site and it was mentioned that careful attention should be paid to this area.
Don
