You can get center mount drawer slides. You may be stuck with that. As you've found out switching drawer glides isn't easy, or simple. In addition to the void inside the cabinet, meaning there's nothing to hang the glide on, you also have to take into account the clearance of the drawer box and the face frame. Side mount glides will need 1/2" clearance on both sides of the drawer box through the face frame. I can't tell for sure, but it doesn't look like you have that space. Undermount glides are out there, but they all have some space requirements under the drawer box, which I doubt you have. So, unless you want to make new drawer boxes, and make whatever inside structure you need, you're best bet is probably to stick with the center mount glides.