code po174 -300-463

What is your question?

I bought this truck knowing i had to replace the head,so i did.hte engin started fine.the cat on the pas side was cloged bad so i dumped out what looked like powder then knocked out the restof the stouf and put it back on.The truck seemed to run good so i took it for a drive. the cheak engin light came on.My scaner sead po174-300&463. Ifound a used fuel pump and sending unit hoping to fix po463.The fuel gage works now but i am still getting that code.Wile driving i could realy fill that miss.I replaced the intake the intake gaskets, spark plugs, The truck runs grate now but the same codes still come up. Queston is bank #2 on drivers or pas side? It seems to controdict what i see in the book. Do you think the outher cat is cousing the proublem or is the one i gutted kot reading the signal? Whill it hert the engin to run it? what is senser circuit high voltage? would realy appresuate any insite with this thanks. kevin