I guess that would depend on how realistic a mount you want. I've read of people having really good results with opening up the abdomen from the bottom and removing the guts and then stuffing with cotton balls, positioning the body, and then allowing it to dry.
If you don't move quickly, Ts are so massive they begin to decay soon after death and they STINK horribly.
I'd like to be more help but the only ones I ever kept I just dried without stuffing the abdomen and they didn't look all that great, the others had the unceremonious burial in the trash can. A living T is a beautiful thing, a dead T is a dead, potentially stinky bug.