Installing Netbackup 6.5 on pa-risc hpux 11.31 server

Need help in getting the installics script for netbackup 6.5 on hpux 11.31 pa-risc rp3440 server. The netbackup 6.5 ICS media for hpux pa-risc supports hpux 11.23 and I'm running hpux 11.31. Any idea how I can move forward with the installation of master and media server? 

Appreciate your help/sugesstions. 

Thanks