Forefront Threat Management Gateway 2010 use it as firewall function only

Hello,

We have Active Directory Site with 700 clients machines with 2 gateways. One of the gateway, we use Forefront Threat Management Gateway 2010 as web cache, firewall server, We are planning to implement WCCP with Cisco L3 switches and use Forefront TMG 2010 as a firewall role only. (I am not sure whether I can disable "cache" role)

Can I disable "Cache" role on Forefront TMG 2010 and use it as firewall?

any recommendations, thoughts would be really appreciated,

kind regards,

Akira Sekine