Slipstream .Net 3.5 into install.wim, Server 2008 R2

This is tested and works with:
en_windows_server_2008_r2_with_sp1_x64_dvd_617601.iso

8dcde01d0da526100869e2457aafb7ca

d3fd7bf85ee1d5bdd72de5b2c69a7b470733cd0a

To work with this solution Deployment and Imaging Tools must be installed:
http://download.microsoft.com/download/3/8/B/38BBCA6A-ADC9-4245-BCD8-DAA136F63C8B/adk/adksetup.exe

This package works nicely on Windows 7, 8.1, 10
1) Extract en_windows_server_2008_r2_with_sp1_x64_dvd_617601.iso to c:\iso

2) Open Deployment and Imaging environment in "Run As Administrator" mode:

3) Create mounting directory (you can nicely select command with triple click):

if not exist c:\mount md c:\mount

4) Mount install.wim to the mount point:

dism /mount-wim /wimfile:c:\iso\sources\install.wim /index:5 /mountdir:c:\mount

5) Enable .NET Framework 3.5.1 feature:

dism /image:c:\mount /enable-feature /featurename:NetFx3

6) Unmount install.wim file:

dism /unmount-wim /mountdir:c:\mount /commit

7) Extract only the index you are really interested. This will allow to save few hundreds of megabytes:

"C:\Program Files (x86)\Windows Kits\10\Assessment and Deployment Kit\Deployment Tools\amd64\DISM\dism.exe" /Export-Image /SourceImageFile:c:\iso\sources\install.wim /SourceIndex:5 /DestinationImageFile:c:\install.wim /Compress:max

8) Overwite CD content:

move /Y c:\install.wim c:\iso\sources

9) Re-create bootable iso image:

"C:\Program Files (x86)\Windows Kits\10\Assessment and Deployment Kit\Deployment Tools\amd64\Oscdimg\oscdimg.exe" -b"c:\iso\boot\etfsboot.com" -h -u2 -m -lwin2k8r2 "c:\iso" "c:\win2k8r2.iso"

10) Remove mounting directory:

if exist c:\mount rd c:\mount /Q /S

11) Remove iso directory:

if exist c:\iso rd c:\iso /Q /S

P.S.:
This image has a lot of indexes so in this scenario it is only working with Data Center edition (index 5):

Index : 1 Windows Server 2008 R2 SERVERSTANDARD
Index : 2 Windows Server 2008 R2 SERVERSTANDARDCORE
Index : 3 Windows Server 2008 R2 SERVERENTERPRISE
Index : 4 Windows Server 2008 R2 SERVERENTERPRISECORE
Index : 5 Windows Server 2008 R2 SERVERDATACENTER
Index : 6 Windows Server 2008 R2 SERVERDATACENTERCORE
Index : 7 Windows Server 2008 R2 SERVERWEB
Index : 8 Windows Server 2008 R2 SERVERWEBCORE