I think I remember there being some kind of dovetail adapter which went on flat ones and then moved the rail to the side and tilted it, you may be able to use it and just reverse the effects. Lemme see if I can find it.
Okay,
found it. It's for weaver rails, and it may not be compatible with the phantom dovetails(I believe there are two different measurements of dovetails, correct me if I'm wrong), but it's a start