Do a walk thru of the forces involved here in your problem, All forces start at the interface between the tire and the road surface. They next go thru the rim, the hub, the spindle and spread out thru the ball joints, to the UCA that attaches to the a bracket on the unibody frame rail, and the LCA goes straight into the K frame. Also keep in mind, the forces are acting on the mass of the vehicle and cornering, turning, inertia forces that mass resists, The largest single most dense mass (engine) on the entire car is located/attached directly to the K frame. Of course other masses, the unibody, interior driver are located away from the K frame and have the advantage(?) of leverage in transmitting their. maybe smaller(?) forces (moment) by simply having less mass. Also don't overlook the fact the mopar OEM K member is the single most robust/rigid single component on the car. So the "weak" link in this unibody system of transmitting the UCA portion of forces into the chasss is the connection noted above. Also understand, these tire/road surface generated forces are divided into the the spindles vertically by the ratio the spindle is located between the vertical height of the ball joints, or about 1/3 UCA and 2/3 LCA. We are disregarding sprung weight which goes 100% into the K Member. The shock loads goes into sheet metal, and only need to resist vertical motion during transients. If the sheet metal flexes with shock loading, it then becomes relatively another "stiff" spring, and can be accounted for by TB choice and shock rates. However this adds complexity in race set-ups, and is not a chosen goal. For that matter, since NOTHING is perfectly stiff on a car, everything becomes a spring, and tuning everything together achieves goals sought. Brake forces are a component in all this, but not a huge concern if everything else is working as needed.

Nobody has made the case to me that lower radiator gusseting solves many real problems, I have read comments about multi post shaking videos, but not sure what the problem is except for marketing. On this topic, I have little concern if my radio antenna shakes on a multi post shake rig, and why I don't make it out of 1.625" CM tubing.

Since all the forces acting on K member come from tires or to the rear of the K member, reinforcing anything in front of the K member to achieve added stiffness, is inefficient engineering design.

Meaning ,solving other problems might be better use of your time, efforts, and money, like LCA 1/2" steel gussets . Don't get me started.