Emissions fault code

Can someone tell me where this sensor is with this fault code P0136 downstream heated O2 sensor (bank 1).Can't afford to pay $196.00 at auto repair shop right now.(01 mustang)

Thanks for any info you can help me with.

Driver's side after the Cat.

Remember ford uses pass side for #1 cyl.Backwards from all the other cars.Rocky

Sorry about that Rocky is correct its the passenger side.

So its the passenger side after the cat.........Thanks again, You just saved me a bunch..everyone deserves a break now and then, you made mine.