10deg ATDC but on the power stroke.
The crank turns two times for one turn of Cam, 4-stroke engine, CMP is timed to Cam.
So there are two #1 10deg ATDC.
TDC for compression stroke, ATDC power stroke, <<< you need cam at this position
TDC for exhaust stroke, ATDC intake stroke
If you remove #1 spark plug and rotate engine manually you can feel air being pushed out of #1 spark plug hole during compression stroke, when TDC mark comes to 0deg that is TDC compression stroke, turn crank a bit more for 10deg ATDC power stroke.
Look here for the rest: Ford Ranger 3.0L Camshaft Position Sensor