What side is bank 1 and which sensor is sensor 2 on a 1998 Chevy 3500 truck? on 1998 Chevrolet 3500 Pickup

There are four O2 sensors on this truck and two cat converters.

2 answers 3 comments
BANK 1 DRIVERS SIDE.O2 SENSOR 2 BEHIND CAT. CONV.
wrong,2 into 1 ex.3 o2 sen..[1500]
WTF is that supposed to mean????
A little bit late with that BS anyway ain't you?
b1 drivers side post catt. why are you changing it?