I went to Home Depo and bought a couple of chrome vent covers, matched them up side by side on the hood and cut some holes. The covers look sharp and it gives the air coming off of the fan some place else to go besides down. I didn't have overheating problems but doing slow steep crawls in extreme temps while running the A/C (I'm old ya know) made the engine run better, I'm guessing because it was running cooler. You can put your hand over the vents and feel the blast of superheated air, but you can't hold your hand there long
This worked great for me and several other friends that did their Jeeps after I did mine.
Good Luck