Can I use my computer monitor set at 6500K and compare it to my TV side by side in order to set the TV to that temperature? It should work in theory, right?
If the computer monitor was calibrated correctly from the factory it would work. You would use the monitor as an optical comparator. However, the problem with that is that even though the monitor has a preset for 6500K, chances are slim that it is even very close to D65. I wouldn't even trust it to get you in the ballpark.