[Leica] It works .. it works not

["Jorg Willems" <jorg@mindspring.com>]

Some time ago I bragged about my new Domke F803.  I complained that I couldn
't use the middle compartment for the 21mm Elmarit and 35mm Summilux using
Leica's coupling piece because it's too short.  Several of you gave me the
advice to glue two lens backs together.  I was almost embarrassed that I
didn't come up with this simple and practical idea by myself.

Finally today I set time aside to do that.  I used two 14269 backs and used
fine sand paper to make their surface even.  I used super glue and
everything looked great.  It works great for all lenses EXCEPT for the 35mm
Summilux!  For some strange reasons that lens doesn't sit tight enough in
the thread.  I am quite sure that it fit very nicely in the back before I
glued it.
I am afraid to use it because I fear that I would drop the lens one day.

Do you have any other (simple, great, practical) advice how to fix that?
Also, anybody that has two 14269 that I could buy?

Thank you Jörg