Updating, Script protection & permissions

I've tried to read all the relevant posts I could find on permissions and updating objects, but am still unclear.

I don't want people to view the scripts inside my objects.
I do want to be able to update those scripts automatically (eg such as with llRemoteScriptLoadPin).

I also want my object to be able to dynamically change linked prims and inventory items.

From what I can read on permissions, I have a problem. To use llRemoteScriptLoadPin, do I have to have script MOD permission enabled? If so, this means they can get in and see my code, doesn't it? If that was the case, the only way I could update my object but still keep it secure, would be to do some sort of trade-in replacement scheme instead?

Secondly, the changing links. Can this be done with the object being NO-MOD? I know you get a permission request when trying to do an llCreateLink, but is that command only valid when MOD is enabled, or does it work on any permission settings?

Thanks. Russell.

do a test of course but I'm pretty sure what's needed is mod on the object not the script itself.

I've never used the llRemoteAccessPin from the outside, but I've used updaters from the inside. It replaces NC, NM scripts in objects quite happily.

Oh, and making a script NC or NM means the person at the far end can't read it - stupid though that may be. You can only read a script if it's C, M, NT or full perms.