P3D Mounting 8-perf slides in 7-perf mounts?

[Peter Davis <pd@xxxxxxxxxxxxx>]

I have a full-frame slide pair I'm trying to re-mount into a 7-perf RBT 
mount.  Does anyone have any tips on how to position the frames?  This is a 
shot of a group of co-workers, and, to get the whole group on both frames, 
the right film chip is hanging outside the mount by about 1.5mm.  I'm VERY 
inexperienced at mounting, so I don't know the rules for this.  I can trim 
off the excess film, but I don't want to do that until I'm very sure it's 
mounted "correctly."

While we're on the subject, any other tips about using RBT mounts?  What's 
that little "I" shaped plastic tool for?  I discovered by trial and error 
that depending on which way I insert the little pin rails, the film 
sprocket holes either will or won't fit over the pins.  It seems I have to 
insert the pin rails to the tiny holes are facing in towards the slide 
opening to get the film to fit.  Other little tips or techniques?

I'm not trying to open a can of worms about how to do proper mounting.  I 
realize that entire treatises have been written on that subject.  (Come to 
think of it, any recommendations?  I've read Harry zur Kleinsmiede's book, 
but that seems to be Realist-centric, and somewhat "light" on mounting 
details.")

Thanks,

-pd
--------
                              Peter Davis
                Funny stuff at http://www.pfdstudio.com
               "The artwork formerly shown as 'prints'."
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