For a couple of years I've had the #475 flex-a-lite II. The kit supplies everything you need. Included is a nylon shroud. No spacers. The reason I installed it was to employ a kill switch on it for mud / water. It works fine in Florida's heat and humidity. I'm not sure about the reversed blade. There is plenty of room between the fan (which is flat against the radiator) and the motors pulleys.
1997 Red TJ
5 speed w/ NP 231, Nth 4.5" lift, AntiRocks front and rear, skids (tummy tucker, front dif, oil pan, GenRite fuel tank skid, RockJock D-60 4.88, Flex-a-lite fan, Flow Cooler pump, Rhino lined tub, American Eagle Alloys, SS LTB's 34" x 10.5 w/Staun beadlocks, Tuffy console, MileMarker Hydra 12000