Migrate SDP from Windows 2003 x32 to Windows 2012 R2 x64

Migrate SDP from Windows 2003 x32 to Windows 2012 R2 x64

Hi ALL!
We use SDP 9.3 Build 9308 on Windows 2003 x32 
SDP is avaliable for 443 port ( https://sd.mycompany.com)
What is the best plan to migrate SDP to Windows 2012 R2 x64&