I am not sure this is the advice you want, however here it goes.
Let the engine cool completely before starting the project.
Take this time to flush the cooling system, replace all hoses, water pump, thermostat, pressure cap and coolant temperature sensors as needed. depending on mileage and condition.
If your replacing the radiator because of a leak and or over heating, take the time to perform a compression test on the engine. before you buy a radiator or any replacement parts for your car.
If you do find that you need a radiator and other expensive replacement parts, go out of your way to completely check you entire car over.
Check the brakes, belts, timing belts or chain, tune up tires, suspension exhaust, check for codes in the computer, Battery and Charging system.
Basically a 1993 Sunbird is not worth investing a lot of money into to it.
So make sure all the major components like the transmission , A/C etc will work well for a while before spending a lot of money on the car.
If your going to keep the car come hell or high water. I suggest purchasing a service manual for your car, a good factory service manual or even Haynes or Chiltons and be picked up inexpensively online at places like eBay or Amazon. you can also check out a service manual for free from you public library.
If your new to this type of work, read the entire section of the manual that covers the type of work your doing before you start your project.
The manual normally covers the needed tools to do the job, Make sure you have all the tools and drain pans etc to do this work. most anything you need that you do not own can be picked up at Autozone or Napa Via their tool loaner program.
If you end up just replacing the radiator, only use coolant-Distilled water to refill it with. Tap water just is not good for a cooling system.