if you remove these files, do you not see errors in the logs?
The OEM files are still there for reference.
The debug files, well, I don't mind, since these are not referenced in an INF and not likely used by a DLL.
(they don't appear in copyfiles lists..)

the 9x files, I left those in, because they are still referenced to in those INFs.
(now, if people tell me that removal does not break the driver load, they can go, but I am not going to edit them INFs)

1. Obsolete files:
    \D\M\AR\TXTSETUP.OEM
    \D\M\C\1\TXTSETUP.OEM
    \D\M\C\2\TXTSETUP.OEM
    \D\M\I\3\TXTSETUP.OEM
    \D\M\I\4\TXTSETUP.OEM
    \D\M\I\5\TXTSETUP.OEM
    \D\M\I\6\TXTSETUP.OEM
    \D\M\S\4\TXTSETUP.OEM
    \D\M\S\5\TXTSETUP.OEM
    \D\M\S\5\A\TXTSETUP.OEM
2. Obsolete debug file \D\M\L\4\SYMMPI.PDB
3. Obsolete Windows'98 driver files:
    \D\M\AD\9\SIISUPP.VXD
    \D\M\AD\9\SI3112.MPD
    \D\M\S\2\SIISUPP.VXD
    \D\M\S\5\SIISUPP.VXD
    \D\M\S\5\A\SIISUPP.VXD
    \D\M\S\6\SIISUPP.VXD
    \D\M\S\7\A\SIISUPP.VXD
4. Obsolete Windows x64 driver files \D\M\V\3VIDEX64.CAT, VIDEX64.SYS, XFILTX64.SYS
5. Obsolete Windows x64 driver files \D\M\V\4\VIACCX64.CAT, VIDEINSTX64.DLL, VIBUSX64.SYS, VIPRTX64.SYS
6.    Would recommend to use these command line switches to compress MassStorage driver pack: 7za.exe a -r -t7z -m0=BCJ2 -m1=LZMA:d26:fb255:a2:lc7:mf=bt3 -m2=LZMA:d19:fb128:a2:lc0:lp2:mf=bt3 -m3=LZMA:d19:fb128:a2:lc0:lp2:mf=bt3 -mb0:1 -mb0s1:2 -mb0s2:3 DP_MassStorage_wnt5_x86-32_7071.7z