First off welcome to the site!

I have a couple questions. You said something about the radiator blowing.. they did fix that? replaced it? Do you know what else they actually checked while they had it? Temp sending unit? Water pump? clogged hoses or radiator? Lastly, why the h*ll did you let them drive your car for 50 miles? You don't need to drive anything to see if is going to overheat, just let it sit there.... man I bet they drove the piss out of your car. lol

When I got my 88 GT it overheated every time I ran it. I put a 160 deg thermostat in it and it was still hot. Turns out my radiator was old and needed to be replaced. I found this company called superior radiator online. They are the ones who make Griffin Radiators, Griffin just puts their brand name on it and charges more. I got a 2 core alluminum radiator, AND a 3000 cfm electric fan delivered to my door for $300 bucks! My car has never overheated since. My car USED TO overheat after 15 min of driving.

Here's what you should do. Replace the thermostat with a 160 deg. You can get them at Autozone for about 10 bucks. Then drain your radiator and flush it out. Refill it. Start your vehicle and let the radiator pressurize for JUST A FEW MINUTES. (DONT OPEN IT WHEN IT IS AT FULL OPERATING TEMP) Look and see that the fluid is circulating well down in the radiator. (So you can be sure that the water pump is good) If it is, drive your car and see if it starts to get hot. If it does, you might need a new radiator. This worked for my car, but mine is a different body style than yours so things might work a little different with your ride. I changed my radiator and fan myself and it was EASY. Any beginner could do it. Post again if you have any questions.

Here is the website for the company I got my setup from: http://search.stores.ebay.com/dissrad_radiator-mustang_W0QQftsZ2QQsaselZ77887202QQsofpZ0
These guys will help you if you have trouble with the install. All they sell is radiators so they know what they are talking about. Their phone number is 586-463-8722.

Sounds like the electric fan might be your problem, but without more information it's only a guess.

Now my 2¢,
If you have a overheating problem, putting a lower temp thermostat isn't fixing it. I've never understood the thinking that a lower temp thermostat is the way to go. When the car was new, it didn't overheat with a 180° thermostat, so why would a 180° therm be bad now? Something else is happening, clogged radiator, kinked hose, bad fan electric or clutch, engine timing, or a bad therm. There's nothing wrong with a hot running engine as long as it's within the specs and the cooling system is working properly.

My point was not to fix the problem with a lower temp thermostat, but to try and fix a low cost problem (possibly a stuck or bad thermostat) and while he's at it, get a lower temp thermostat. With these cars that we modify, I think it's always better to have lower temperatures under the hood.

You probably shouldn't go lower than 180º. It can cause oiling problems, as well as not being warm enough for the computer to work to its full extent.

yup....180 is the way to go....195 or so was stock

I definitelly agree. 160 is to low for a daily driver. I drove in a car with a 160 stat one time Hope you don't plan on using your heat, it is almost non existant! lol

My heat is sometimes slightly insufficient with the 180º, and I've got a recent heater core. I had a 160º in my '84 and the heat was nonexistent! And it had a new core too. 190º is the way to go in the winter, with 180º being best for the warmer months.

My car's overheating woes

I have had so many problems with my 95 Cobra overheating, but this has not been limited to one thing. Check the wiring on your electric fan mine wore out and it only appeared to be running all the time. These plugs run about 65.00 but will save you an engine if this is the problem. Check your hose and make sure that it is somewhat flexible when the radiator is opened up. If the hose is solid this might mean your system is not cooling properly due to blown head gasket worse case scenario. After a second rebuild my 3 core radiator, intercooled, supercharged beast still overheats. The cause of this is now because there is not enough air flow for the radiator and my AC compressor creates 15 degree difference in the engine. With all the problems I have had in overheating it all boils down to airflow.

Airflow is the easiest of all cooling problems to fix as long as you don't mind dropping some cash on a more powerful fan unit. I've seen some monster electric fans on Summit.