I have a single plug outlet exposed to the elements on the outside of my house. I want to replace it with a new gfi and outdoor cover plate;however, when I tried to remove the existing cover plate nothing seems to move. Actually, it feels like the whole box in the wall is moving. Anybody, changed one of these? Is there a trick to getting the plate off?
First, assume you've turned off the power to that box. If not, do so.
Those covers are just held on with #6 screws in most cases. Some times one, other two screws.
Think the female thread of the conduit box is gone. If original Eichler, it could be a phenalic conduit box (plastic with filler). Some were made of metal. In anycase, the threads are gone and/or the screw thread is gone.
If you feel confident if the need to replace the conduit box, I'd just tear the cover off in pieces if necessary. Or drill out the screws, but that is tough and will almost destroy the cover in any case.
Then replace the conduit box, as the threads are most likely gone. That will require pulling the siding off enough to access the studs and install a new box & wire coupling (tube and rod is the norm and no conduit in this area and dependent on era of Eichler).
Not hard, but you do need to know what you are doing. An electrician is best if in any doubt.
If you really want/need a GFI on that circuit, check to see if they make a GFI breaker for your power box. Most likely not if it's the original power box (fuse box, circuit breaker box, etc).