Re: Fixing warped pickguards
The oven trick, you might cringe at, but that's probably a much easier, much more effective method. If you sandwich the pickguard between a flat surface and a heavy surface on top of the p/g, then you could keep the oven at a low temperature, warm up the plastic, and the weight of the top piece would gradually bend it back into flatness. Of course, you have to be really careful about the temperature. Too hot, and you might have pickguard soup casserole.
If that's too unnerving, the hairdryer will give you a bit more control, but make sure to set it at a wide dispersal pattern...if you concentrate the heat in one spot, it could warp even further (in a non-desirable way). With the wide dispersal pattern, keep going back and forth. What you're shooting for is to warm up the whole pickguard so it gradually bends back to flatness. It'll take a long time, probably. Be patient.
Perhaps the place you're storing this guitar has a heating duct or pipes going through it? Can't say I've ever seen a pickguard warp that badly from just sitting in a case.