I'll give my honest opinion of these upper x-panels, though I'm glad to have them, and that area of the car now looks more "complete":

1 - The intent of the four required pieces of the baffles was to completely surround the radiator opening (on all four sides, top, bottom, left,right)and force all air coming through the grill directly into the radiator. With just these two upper x-panels, the intent is not truly met.

2 - To be honest, the upper x-panels make only a marginal contribution to this plan. With a serviceable hood heat blanket, and the hood closed, there is less than a one-inch gap between the blanket and the radiator support. I tested this with a large sponge and chalk. The gap is less than one inch, so air coming through the grill really doesn't have much room to go "over" the radiator support and be supposedly wasted.

3 - The REAL benefit seems to be the two "side" panels, to the left and right (and in front)of the radiator, of which I do not have. Those two pieces, in my opinion, would certainly funnel alot of air {otherwise floating around the sides of the engine compartment) directly into the radiator.

I'll take a stab at making these with some simple sheet-metal and rubber edging. The hardware points are there on all of our birds, it seems.