Mission Accomplished
I finally got the tire seated on the Zipp last night. Gentle persuasion (and a really stiff nylon tire lever) helped the last bit of bead jump onto the rim. Now, getting the tire off may be another issue, but for now it's on and looks sharp. By comparison, the Mavic Comete disc back wheel buttoned up with no problems whatsoever.
I think I'll consider swapping out that Velox cloth rim tape the next time I have that wheel opened up. There is definitely a combination of tall rim walls and no low area for the tire bead to move into to aid with seating the tires on the 808's.
Hed Disk
I think I'll stay away from those rim strips. As hard as it is to mount a tire on my 808 front, the Hed Disk rear is worse.
Now that you're an expert maybe I'll come to you to have them mounted up next time. :)
-- Mark