[GODZYLLA]

it can be done replacing lang files with dummies in media3.cab and media4.cab and also recompressing media1.cab and media2.cab for additional space saving using this script in a .bat file (this script is used for dummy replacement too):

@echo off

SET /p des=Type cab name without extension: 
SET cab=%des%.cab
SET ddf=%des%.ddf

if exist %des% del %des%
if exist %ddf% del %ddf%
md %des%
echo .OPTION EXPLICIT >%ddf%
echo .Set CabinetName1=%cab% >>%ddf%
echo .Set DiskDirectory1=%des% >>%ddf%
echo .Set MaxCabinetSize=2048000000 >>%ddf%
echo .Set MaxDiskSize=2048000000 >>%ddf%
echo .Set InfFileName=del.me1 >>%ddf%
echo .Set RptFileName=del.me2 >>%ddf%
echo .Set Cabinet=on >>%ddf%
echo .Set Compress=on >>%ddf%
echo .Set CompressionType=LZX >>%ddf%
echo .Set CompressionMemory=21 >>%ddf%
for /f "usebackq skip=5 tokens=2* delims=\" %%I in (`extrac32.exe /e /l %des%\ %cab%`) do (
echo %des%\%%~nxI>>%ddf%
)
echo Make md5/sfv or edit ddf/files if needed before continuing...
pause
makecab.exe /f %ddf%
for /f "skip=11" %%I in (%ddf%) do del /F "%%I"
del del.me1 del.me2

SET des=
SET cab=
SET ddf=

pause

also, in DirectX folder keep only DXSETUP.exe, DSETUP.dll, dsetup32.dll and in GFWL copy DXSETUP.exe and rename it to gfwlivesetup.exe

size after conversion: about 3.09GB

EDIT: media3 and media4 dummies: