OK, so my o2 sensor finally gives up at 158k on my '90 v6 4X4 extracab and I have the new on setting on the workbench. A quick visual of the old one shows the pipe and well (nomenclature?) to be in good shape, studs look fair but the retaining nuts are corroded into a round cone. I was thinking Dremel to remove them but figured I'd ask here first for some BTDT advise.
Gary W.