FYI: there ain't no such animal. The searchlight that you were seeing on the M60 was IR based, and was used by the light-amplification night vision sight used then. As an aside, the M60A3 was far enough behind the times that it had to use "frog eyes" to get the range to an enemy tank before shooting: the "frog eyes" were visible immediately above the smoke grenade launchers on the turret of the second picture on the first page of the link you sent. They actually had to use trig and parallax to determine the range before the M1 brought out the laser range finder (the M60A5 incorporated the laser range finder as well as a few of the other goodies that came out on the M1).
The first flight M1 included a true thermal night vision system for the gunner, which allowed them to shoot at night without lighting off a big "Shoot Me, Please" sign on top of the tank. The driver and loader both had light amplification viewers that could be swapped into one of the periscope mounts at night. These LA viewers worked on ambient light only (they came with IR filters for the tanks' headlights, but I think we only used 'em once or twice).
I changed my MOS from 19K to 67R before we got M1A1's (much less M1A2's, if that tells you how old I am), but IIRC, the M1A2 has a second thermal viewer that allows the TC (tank/track commander) to operate independently of the GPS, allowing hunter/killer ops between the TC and gunner. There were rumors that they were going to include true thermal systems for the driver and loader, too, but I don't personally know if that came to pass.