O2 sensor locations......?

Just want to confirm my thoughts & questions on a 2001 L series with the 3.0 V6. This thing is setting 02 codes all over the place. 0171, 0174, 0172, 0175, 0134, etc.

I know sensor one should be before the cat & sesnor two should be after.
My question is, is bank one always the front towards the grill & bank two always the rear towards the firewall?

Thanks!

Eh, this is the S-series forum. L series are totally different cars.