Why not reinforce the K frame at the same time? Several benefits here,the least of which is added strength. Welding a K frame solid makes a difference in handling,chassis stiffness,motor mount solidity,less steering deflection,etc etc.
The kmember is a good thing to brace. The steering box mount is very weak. With the can on the ground, just have someone turn the steering wheel from lock to lock and watch how much the steering box moves in relation to the kmember. Actually the whole front end is like spagetti!