Where do you change the oil on a 2002 Zr2?

I'm assuming you're asking where the drain plug and filter are?

The drain plug is at the bottom of the engine oil pan, it's a single (5/8") bolt facing the rear of the vehicle. The skid plate is right below the oil pan but there is a cut-out on the back side of the skid plate around this bolt so you don't have to remove it. It may be painted yellow, but the paint might not still be there. Just for reference sake the transmission is directly aft of the engine oil pan. The transmission pan is a large (12"x14"?) flat pan with no drain plugs and it kinda looks like a baking pan with funny edges.

The filter is under the front part of the engine, behind the front skid plate. there should be an access flap built into the skid plate so, again, you don't have to remove the skid plate.

if this isn't what you were looking for please clarify your question.