Seat swap question

I've got my new seats out of a cavalier, but I'm having issues with getting the old seats of the mounts and sliders. I've sprayed with pb blaster , used a cheater bar, tried a hand impact driver, but all i am doing is just breaking the torx bits.
Does anyone know what the dimensions of the bolts that attach the sliders to the seats, and then to the mounts? I want to pick some up before I go after them with with destructive methods.

Thanks!

Seat swap question