Hite used the Flex-a-lite 180 (Note: his write-up says 180, sig says 183, they appear to be the same besides Summit listing the 183 as a Dodge-specific fan?). Seems like a better choice, though there is a $65 price difference
http://www.lincolnvscadillac.com/forum/showthread.php?68306-Cooling-Fan-Replacement
Flex-a-lite 168: $265 @ Summit
15", 8 blades, 3,000 CFM, 19.5Amps, No AC circuit
Shroud: 18h x 16w x 4.250 thick
Flex-a-Lite 180: $330 @ Summit
15", 8 blades, 3,300CFM, 18A, has AC circuit
Shroud: 17.5 x 21.5 x 4.187 inches
Here is a stock Gen 1 fan+shroud
Stock Gen 2
What you can immediately notice is that the stock shrouds are wider than they are tall. Now, I can't currently measure the dimensions of my stock hydraulic setup, but the 168 is barely wider than fan itself. Sure, you could probably mount the 168 sideways, but it's still smaller than the 180. The FaL 160 instructions mention filling in a bunch of gaps. Some things to consider...