1999 Tahoe Overheat

[Already Gone]

About 2 weks go i took my 1999 Tahoe (5.7 Vortec, 4L60, full Police Package ) and since it just went over the 100,000 mile mark had the orange antifreeze changed to the green and a new thermostat ( Stant ) installed. I've only done about 100 miles since with driving around the City since I had that done. This morning I headed out of town and about 30 miles out my temp gauge starts to really go up. I've seen that before so keep driving but the gauge kept climbing. When it hit 260 and I pulled over and shut her down. Lifted the hood and saw a little water, not antifreeze, dripping on the pas side from near the air cleaner. I dint blow a hose and no antifreeze leaked out. Truck would turn over but not start. Called a tow truck and he took about an hour to get there. Just before he hooked up I checked ans temp gauge was down to cold. I tried starting the truck and it started but ran rough and I didnt hear any obscene noises from the engine. I am clueless as to may have happened here, has anyone got an idea. Oh yea its a California vehicle if that makes any difference cause of the extra emissions thing. Hopefully I didnt lunch the motor.