Help with Juniper EX

I'm preparing to monitor our Juniper switches via OpManager and after reading the posts for Juniper i'm still a little confused on what to do.

I know I have to place the mibs in the correct dir on the opmanager server and I have a way to import the mibs into an snmp walker so that is not the issue. I downloaded the mibs from Juniper but they're in txt file format, not mib. Do I need to convert them to mib or cfg files? If so, how? And what mibs so I need? I want to start off with basic stuff - cpu, memory, temp, etc - but will add more as time goes on.

If there is any step-by-step documentation from OpManager or other members who can offer advice, I would appreciate it.

Thanks.