Your oil light (1st gen) is located right under the seat belt light. When you turn the key ON, if the oil light does not illuminate, you have a bad sender, and need to replace it immediately. Easy to change, and inexpensive. Right above the oil filter on the front of the engine. I used the AC Delco part, it took about five minutes to change, including grabbing my tools. My oil light worked immediately after replacement.
OIl light symbol:

Should look like this:


If your cluster does not show the oil light when you turn the key, you have a bad sender.