Used a thread chaser (bought for $15) and the new ones now in place. Not a five minute job - more a five day job if it doesn't shift on the first turn of the spanner! Oh and I need to replace a work bench vice that broke in half when trying to undo the old sensor - thats how bad it was!

 

Got my cat off finally and working on the O2 sensor removal. While reading old threads, it is interesting reading this last thread since I broke by work bench vice in half trying this morning. Will continue soaking and hopeing will get lucky in the next couple of days.