[Leica] how do i take apart this voigtlander 35 1.7?

[Kyle Cassidy <cassidy@netaxs.com>]

hey kids -- while in a sewer in bucharest (don't ask, i'll tell you later)
i smacked my leica against a stone wall while climbing over a huge water
pipe -- the camera is fine, but the voigtlander 35 1.7 that i had on the
front took the full force of the impact -- the lens works, focuses
properly, etc, but the front is loose now. if you grip the f-stop ring,
you can rattle it around -- more play than i'd like in the lens. i'm sure
it's just a screw that i have to tighten somewhere, but for the life of me
i can't find it. 

there are three screws in the back where the screw mount is -- they seem
like the only option, well, either that or the tiny standard screw on the
focus mount.

any advice? ("yeah ya jerk, take it to a qualified camera repair person")

thanks,

kyle