How to replace 1997 buick inition coil

I just did one the other day. There are three coils. You can determine which one is bad by using the number one spark plug wire and an old spark plug. Put the spark plug in the wire ( while it is still in the coil) and ground the plug against the engine block. Make sure it is grounded solidly to metal or you could get a nasty shock. Have someone start the engine. Look at the spark. It should be fat and blue. Turn the engine off as soon as you have seen the quality of the spark. Pull one of the wires from each coil in sequence and move the number one wire to that coil. Proceed as above. The weak coil(s) will have intermittent spark, yellow spark or maybe none at all. Once you know which coil(s) are bad remove the two small screws at the ends of the coil. They hold the coil down. Pick the coil straight up, pulling the contacts out of the ignition module. Set the new coil in place and screw it down. Both towers spark every time the coil fires so reinstall the wires in either spot on a given coil. Good Luck