If you get the panel off in one piece, I've had good luck rejuvinating brittle plastics by applying a thin coating of ABS plastic glue thinned with MEK (applied to the back side if possible). I've always rolled it on with a small trim roller, but I've also wanted to try thinning it enough so that it would be sprayable with one of those little spray bombs. Of course a well ventilated area and appropriate PPE are a must when working with this stuff (charcoal-filtered air, with lots of fresh air). I've recently purchased a 3D Pen for my kids, and I think with some black abs filament you could do some nice work with it... I have found that the self-adhesive fiberglass tape used for wallboard joints works pretty well, and stays in place well enough to wet out and let the bonding action work...
I have some pics of the panel overlays that I repaired after rearranging the panel on our plane, check out the This Old Airplane facebook page...
Cheers!