Just to say that I do like low angle shots at weddings. For a start it gives you an unusual perspective, but the greatest boon I find is that you get rock stability. I can quickly whip off one of my shoes to use as a bean bag, press the Z1 down hard into it, flip the top-screen upwards and shoot away.

Just off the top of my head...could you use a "super clamp" with a ball type head, clamed to the pew end?

I use a superclamp with double ballhead all the time. Ideal for clampin on pipes/railings/tables.
Manfrotto nr. 035+155+143