Mounting ECP Application Databases Read Only

Hey guys

We have a need to mount remote databases using ECP, but with the Application servers mounting some of the remote databases as Read Only.  The Data servers will keep them R+W as normal.

From what I can gather this isn't possible using a "Mount Read Only" option, it looks like ECP just inherits the Database servers settings.  My reading seems to require roles/access/permissions to enforce Read Only on these remote mounts.  Does anyone have an easy guide/cheat sheet to set up read only ECP Application server read-only mounting using roles/permissions?  Or an alternative method to achieve the same goal (using ECP, we've ruled out shadowing/mirroring for this specific task)

Cheers

- Dave