[kitcarbp]

Dave, I would install the Taurus fan first and re-check temps. Near 4,000 cfm's through the core will help. And then have your existing Griffin rad cleaned if you suspect restrictions. I would call Griffin to see if they would service the rad instead of relying on a local shop who may not have the skills. Remember these rads are rated to cool at the engines max engine power, not sure if yours is a track or street car but you spend so little time at max power if its street car, existing rad should be OK if not clogged. BTW, you want to go wider first if you can before you go thicker on the rad core. I just had a custom rad built by Griffin and fit a 16 x 26 core size with narrow tanks about 2.25" wide each using 1.25" wide tubes. my 2 cents. T-stats- boy I noticed the quality varies. I also liked the OEM FORD T-stats that use stainless components and use a steel ball check valve to allow air to bleed out. I purchased a STEWART 180 with air bleed holes already included that seems well built (Robert Shaw mfg).
Remember it only indicates temp the therm opens, not what temp engine runs at. Engine temps will depend on Ambient temps and load but 190-200 F engine temps in the 90's is good. As ambients climb to 100 and 105F you should see 210-215 F engine temps as normal. If you can keep engine below 220F (under load driving) in an ambient of 110F in TX, AZ or CA you are in good shape.