Nikon Coolscan 8000 question

[william_v_nicholson at yahoo.com]

A while ago there was a discussion about modifying the standard film
holder (called the FH-869S) for the Nikon Coolscan 8000 scanner in order
to hold larger electron micrographs.  Masahide Kikkawa mentioned that
Nikon Engineering modified a film holder to hold larger films up to 9 cm
in width.  Nikon make two other film holders - one with glass (FH-869G)
and another film holder that can rotate which also has glass (FH-869GR).
Has anybody modified these other Nikon film holders with glass to hold
larger films?  Also, is the glass any use for flattening out the films?
Why would anybody want to rotate the films?
William