Bill, I think you are going to achieve unanimity on this issue. Get the radiator flushed. Its inexpensive and easy, and could save you gajillions of dollars if it is clogged, which it probably is, to a greater or lesser extent. When I got mine done last year, it was only $40 and I was told it was 40% blocked. Unfortuantely, this was AFTER the head on my 392 Hemi cracked. Bad timing. I agree with Dimitrios. By-pass or remove the water filter. I know of no purpose for it. I do regularly change the coolant in all my cars. The water here in S. Texas is loaded with lime scale and other junk. My old, deceased, VW would not have made it to a quarter million miles if I had not had the radiator flushed at least once a year. I advise you to change the thermostat, too, while you are about it. No point in letting the failure of a $3.00 part ruin your engine. You cannot lose with getting the radiator cleaned. Chances are that they will repaint it too, as the old paint won't survive the cleaning process. I just hope you have more romm to work with on the 413 equipped 59 than I have on the 58. There is no adequate replacement for the fan clutch in my application, as the disatance between the water pump belt housing and radiator is so miniscule. Hugh