Peter,
See below
1: on ASR and 7600 GRE tunnels, Apply
ip wccp 61 redirect in
ip wccp 62 redirect out
2: Create a seprate (new) subnet for WAE on both routers and apply "ip wccp redirect exclude in" on this new interface
3: Configure WCCP globally
ip wccp 61
ip wccp 62
Best to use latest code available for ASR and WAAS. You can chose to use redirect-acl with global WCCP services if required.
You are all set for initial testing.
Ahsan