How do you change items into various other types? for Instance, can you use the Iron claymore mesh as an activator without opening up the BSA and taking out the mesh?

Well, if you have a box version of Morrowind, the second disk contains all meshes in unpacked state.

There's another, crooked, way - you take the iron claymore item, write down its mesh name, then create an activator with whatever dummy mesh you take, save the mod, open it with some third-party utility (Enchanted Editor, or MWEdit, for example, though for this particular task I personally prefer TESPCD) and manually edit the mesh name into your activator's mesh field. You're only recommended to use this way, though, only if you *really* have no way to extract a real mesh - it's too easy to screw something up if you're not well-experienced with mod editing.

OR he simply calls a random mesh "iron claymore", imports it from the meshes\w file as an activator and erases the nif file.

Hah!

I tried that before, didn't work

Wierd, worked for me every time. ;shrug: