I came across this - https://www.ms4x.net/index.php?title...s_MS43_CAN_Bus. All should be accurate if your car has an L6 and is still likely to be accurate for the V8.

No info on decoding the injector pulse width from the two bytes, but it says:

DME4 0x545
Byte 1 - FCO[LSB]
Byte 2 - FCO[MSB]
Fuel Consumption

If you do happen to have a V8 it would be the N62 since yours is a 2005. That motor does have wideband O2 sensors.