I have installed them in a couple of my Pintos. They are not hard to do as most come with the zip-ties to mount them on the radiator. You have to decide if you want one that comes on automaticly, a full manual one, or one that will let you do both.
My question back to you is why do you want to do this?
Some people remove the stock one to get more power from the engine(like me), others install them because they think that electric ones just cool better.
Mechanical fans, like the stock ones bolted to the waterpump, provide the best airflow.
Most electric fans do a better job 'pulling' than they do 'pushing'.
The fan is very important to the survival of your engine, this might not be an item to 'cut-corners' with.
Keep these details in mind when you buy one.
Bill