I am just going through the commotion to install a number of scopes here - which threads do you mean? I have screws into the receiver to hold the bases to receiver; I have cross bolt screws to transfer recoil and I have ring cap screws to hold the scope tightly. Or are you meaning that the scope bodies have been "glued" to the rings??
My guess for "glue" is that you will have to figure out a way to make it let go without wrecking the components - maybe brute force to "crack it"; maybe heat to melt it; maybe chemical to dissolve it? Kind of hard to guess what will work without knowing what the glue used was, though??