I replaced one on my dad's 89 Olds last year. Here is what I suggest. Take out the whole thing. The coil packs sit on top of the ignition module, which is flat and has a couple of sets of wires. I tried removing the coils first, bad mistake as this caused more trouble than worth as the coil bolts are near impossible to deal with. To remove the assy, you have to remove the larger bolts that hold the module down. I do not remember for sure, but I think 2 or 3 hold it in. Be careful when removing it as your crank sensor is actually attached to this thing and is inside your engine block! It is several inches long and most likely will crack when taking out. You need to replace this anyway to avoid future trouble, but don't want to have to fish for the broken pc. Take this out and have it tested (the module) at any Advance or NAPA. If you have lost a coil the rest is most lilkely ready to go. And given this is a major pain to do, if money is not an issue, then replace all of it anyway. Module around 80 bucks, and sensor around 20. You already have a new coil I assume so get another one. Bolt it all togther and install as one assy. You might want to get a helper and a small mirror to help you with this. I ended up unhooking front motor mount and lowering engine to even have enough room to work, even with help. Hope you have more room than that.