The car overheated about 2 weeks ago. had no idea why. fluid was full, so we just took out the thermostat temporarily since it is summertime. has been fine since then till tonite when it all of a sudden overheated. put in the new thermostat and gasket, topped off the fluid and still overheating.

they are not qualified to repair a wheel barrow
your son is wasting his money and time dealing with them
the first test for overheating is a compression test to check for head gasket or cracked head/s
water pumps do not cause over heating as they are only water circulators
thermostats often do and if not installed correctly will still cause a problem
find yourself an accredited service center with experience on your make of vehicle and get a proper diagnosis and quote

wild guess , clogged rad tubes.
wild guess 2, pump impeller , rusted to near nothing
lots more,,, why guess, get the car serviced.

Sounds like your thermostat isn't opening properly

Its possible you had some air pockets in the cooling system from replacing the thermostat.
I would check the radiator cold from time to time to make sure it is full.

Sorry to say you probably have engine troubles.
A leaking head gasket will drink the coolant and cause the bubbles to form.
A mechanic can check for leaks by pressurizing the cooling system and also checking for exhaust gas in the radiator.

It sounds like the fan is bad. Cars with a/c usually have two fans, so when you turn on your a/c that fan kicks on cooling the fluid/engine. And even if the fan is working it might not be working at full capacity. know more about diagnostic tools from http://www.obd2express.co.uk

So I took it out myself today to see ? took what out ,to see what ?
Do the cooling fans work ? Could be the step motor that controls the temp. gauge . How are you determining that the vehicle is overheating ? Gauge on insturment cluster ? GM had bad step motors inside thier insturment cluster's . 2003 to 2006 ! Your best bet , take it to GM dealer .

SOUND LIKE COOLANT FANS HAS A FAULTY THERMO SWITCH LOCATED AT THE BOTTOM OF THE RADIATOR ON LEFT HAND SIDE.CHECK THE FUSES 8 IN THE ENGINE COMPARTMENT AND CHECK FUSE 16 IN THE PASSENGER COMPARTMENT FUSE BOX.WHEN ENGINE OVERHEATING IF BOTH COOLING FANS WORKING.OVERHEATING PROBLEM COULD BE BLOWN HEAD GASKET.CHECK ENGINE OIL LOOKS LIKE MILK HEAD GASKET LEAKING.SEE WHEN YOU DRIVING LOW AND HIGH SPEEDS THE COOLING FANS SUPPOSE TO BE RUNNING.IF THEY NOT RUNNING THAT IS YOUR OVER HEATING PROBLEM.

Problem with this is that it could be a number of things, have ur water pump checked, open the radiator and see if there is water running through it, a bad or plugged thermostat, in this case it does sound like a blown head gasket. id suggest flushing the radiator with some cleaner that u can buy at the store and check n see if ur thermostat is stuck, hope for the best and expect the worst

i would try a new thermostat and a good rad flush, and if your running dexcool switch to a green type (prestone, motomaster)
that worked in a ford taurus for us