I was thinking to add another bit to the f but I am not sure if that would be the best thing or can the ALU already do NOR in some combination it already has?
I did add look ahead carry to my ALU and over flow detection. The ALU test that was given and now I am adding a test for the over flow even though I did verify it manually. The over flow detection is built into the adder.
Since the ALU can independently invert the inputs and output of the AND operation various combinations of nx, ny and no with f=0 will compute NAND and NOR, similar to how OR is computed. Remember how you built your OR gate in HDL.