74 Challenger, 318/904 upgraded with 340/360 like cam, 600 cfm 4bbl, dual exhaust. I replaced the stock radiator with an aftermarket aluminum one "rated to 375hp" (supplier's rating) from Radiator Express. Dims are 17" x 22" a 1 3/4" 2 row. I'm also running their electric 16" fan mounted to inside so it sucks air. Do I need a shroud? I have consulted Mr. Google images and everyone seems to be running electric fans without a shroud. What do you guys think?

Thanks
Scott