Isa 2006 installation

Hi,
i want to insatll Isa 2006 standard edition with single network adapter. My network Scenario is

Internet (DSL)->rOUTER->pIX (PAT)->sWITCH->iSA.

i have allow one ip in pix firewall for access the internet and assign this to isa i.e 10.x.x.x with DNS 202.163.x.x. My network ip are also 10.x.x.x.

Please guide me to how can i install isa with my network scenario.