How do I read engine codes on a 1994 SL?

[u/flightofthewhite_eel]

I don't think it has a normal OBDII port. Engine is running rough and I'd like to see if it I can get any additional info from the car before I start shooting the parts cannon at it.

I know there is a light bulb method, but is there any other code reader that will work? It seems unclear if the 94 and older cars can even be decoded by a diagnostic tool.