Use small carp hooks with whatever set up/rig you use, size 12 - 6 (it's helpful using a type of pennel rig with two books close to each other) and when you get a bite don't strike for a couple of seconds, let the gilt take the hook a bit deeper to get a good hook hold.
I've had some luck using a bunch of isome or artificial crabs (gulp are good as they stink).
Will watch this with interest. Its on my to do list. I've been thinking about it and a gilts diet is very similar to a wrasse and the mouths look geared up to do the same job of crushing shellfish, so was thinking maybe the same methods of hrf for wrasse with a creature bait would work for gilts. Same as all fishing its probably 90% down to finding feeding fish..........
Big bream will require a good hook and will crush large crab (3 inch across back) on a 1/0 no worries at all. Sakuma manta or a crab pattern will do. My lads hooked into a couple of brutes on the xl isome. Good luck.