Following IIS 8.5 features are required for SMP, Package and Task Server installation on Windows Server 2012 R2.
As of ITMS version 7.5 SP1 Package Server automatically detects the list of IIS requirements and posts it as a Warning entry in the Symantec Management Agent log.
NOTE: ITMS 7.6 and 8.0 require .Net 4.5 and ASP.Net 4.5 in addition to .Net 3.5