you shouldn’t have to upgrade any of those bolts. The OEM bolts that secure the bearing support race to the arm are fine(those large torx socket ones you have in there and marked) In the box I had six long black grade 12.9 allen cap bolts and matching washers that bolt the bearings to the bearing races. You want to use those.
You shouldn’t have to buy any hardware for those t-arms to bolt the bearing up. I provided all that in the box. 