Selective materia retrieval?

I have an item with two slots and one materia that I want to replace, but it's the upper one in the materia retrieval window, but the bottom one is selected.

Is there any way to just pick which one I want to retrieve?
Or do I have to remove both, hope the lower one isn't destroyed, then pay to meld both of them.

You have to retrieve it in the opposite order you melded it.

Newest meld is always first removed. One thing to remember, if the materia is tier 4 or lower you always get it back(tier 5 you usually get back, tier 6 you sometimes get back).