Thanks to Niceguy, I called the dealer service department and got an answer. According to one of the mechanics, 1988 was an odd year that used either a battery or a reset switch. According to the mechanic, both were "stupid." The service department said that if they had to reset the Maint Reqd light it would be $84.00 to replace the battery and $48.00 to flip the switch.
I figured I could screw things up cheaper than they could so I dove in.
Step 1. Remove 5 screws and remove the lower dash cover below the steering column and below the headlight switch.
Step 2. Find the blue box under the headlight switch. It measures about 3x4 inches.https://dodgeforum.com/photo.asp?pho...=6&apage=1
Step 3. Carefully wiggle the box offof the tang it is attached to. You will put it back when done.
Step 4. One end of the box has a large rectangular opening you should be able to see easily. I assume this is where a 9v battery would fit. Mine did not have a battery, so I began looking for a switch.https://dodgeforum.com/photo.asp?pho...=6&apage=1
Step 5. There is a smaller hole that allows you to see inside of the box through the battery hole. (see photo). Just inside of this hole you will see a small micro switch. The micro switch was the push button type.https://dodgeforum.com/photo.asp?pho...=6&apage=1
Step 6. Start the car and use a pencil or some other similar, non-conducting tool to gently press the button. Your Maint Reqd light should be out.
Step 7. Reassemble your car and count the money you saved.
Tools I used: phillips head screw driver, paint brush handle (to press the button) and a drop light to see.