P3D TDC 116 & 2x2x2

[rod sage <rsage@xxxxxxxxxxxxxxxxxxxx>]

I own a TDC 116 and have always wondered what TDC had in mind when they
made the the slide carrier back slot for 2x2 slides. Was it mostly an
easy way to show single mono slides or did they have a special type of
mount and viewer in mind for full frame stereo. 
I have saved my toss-out slides, cut off the left and right verticles
which are 1/2" wide and taped them between the two 2x2 slides to project
in stereo. It works fine, but then I have no viewer in this format
(2x4.5) to look at them with.
Were there ever any viewers in this format?
I know Reel 3-d sold slip-in mounts in this size, but had no viewers
that I know of.
Rod


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