They found out the getrag 6sp wouldn't fit, didn't realize the stock 4sp could be put on with a little work (but that hemi making 485hp the 833 may not like it in stock form..) and they had a T56 6sp on the shelf - they went with the T56 not a 5 speed.. these guys also do not get paid by Discovery, just like the street outlaws guys do not get paid..