my experiences, if its a 5sp look on the driver side kick panel to floor board. Lots of know leakage from resevior of both clutch and brake. middle of the truck under the heater core, known for leakages and rust. both rear 1/2 panels, people never pay attention and someimes water leaks in and fall to the rear and builds up. lots of rust there. check around the windshield area as lots of people put glue and cover up winshield housing.