I have the 2.5 in my TJ, I am thinking it is the same. I just changed mine, There are a couple of nuts to be removed holding on the electrical wires. then there are two bolts going vertical from the botton holding on the starter, on my TJ they are those wierd reverse torx type heads on the bolts.
Then the starter should just pull right out. I don't think there is any way the pan has to be removed. Maybe the starter is jammed somehow to the block. a few gentle taps should help persuade it off.
If you pick up the replacement starter first you should be able to see how it goes on. This will mean two trips to the parts store to get your core charge back. But Olds isn't that big.
