Quick internet search revealed the answer.
The oil filter is located at the bottom of the engine. Look underneith the front bumper. You will see a hole in the scratch plate undernieth. It is located right in the hole on the bottom of the engine.
It is under the backseat.
The oil filter for a 98 Olds Regency is on the side of the engine. The filter is a screw on type.
Motorcraft ( FL-820-S ) engine oil filter
Does stp2808 fit 98 civic1.6D1y68
Haha is this a Joke??
Above the oil filter
Either the oil filter was not tightened enough, or it was over-tightened and the seal ruptured.
The oil filter is relocated to the front drivers side bumper.
On my 98 Ford Expedition the oil filter is located on the driver side behind the front bumper.
On the passenger side of the engine
98 mustang 3.8L v6
4 qrts w/ filter