High Volume Water Pump

I'm thinking of buying and installing a high volume pump on the 383 and am wondering if anyone has experience with the change over as far as problems other than getting the right thermostat. Changing because the stock one has a seal leak and I need a little better cooling for idling around town, cheaper than a custom made fan shroud.

Looking at this one http://chucker54.stores.yahoo.net/brbhigvolwat1.html

Terry