Re-Designing with hybrid materials of Bracket is required...

Your task is optimizing a bracket, see dimensions in attached file, Soft form of bracket is also attached separately in the attachment. The bracket is massively over-dimensioned and it is your task to make it as light as possible. Starting weight is 8,2 kilo. It is mounted on a stiff plate on the bottom surface and 4 M10 bolts are tightening it, the tightening force you have to look up in a suitable table. We have 2 static forces (20KN) acting on the top of the bracket, see picture below. You are allowed to remove any material not necessary for the purpose of the bracket. How would you reason for a suitable choice of lightweight material and the design of a new lighter bracket? The digital file is available as a step file. It is up to you and your new design to make sure that the material limits are within its limits. The safety factor for failure is 2.