Apr. 1, 2015. TDK Corporation has announced that its Hong Kong-based HDD head manufacturing wholly owned subsidiary, SAE Magnetics (H.K.) Ltd.
You use a wrench to screw, or unscrew a bolt. A screwdriver is for screws. Either way you turn it left. Some bolts have reverse threads and would turn the other way to unbolt.
Try unscrewing the tub faucet itself. I am replacing old brass trim also and couldn't figure out how to remove the faucet from the roman tub. It has no set screw. I had a plumber take a look and he finally twisted the entire faucet counter clockwise and it unscrewed.. You don't have to turn the water off to remove the faucet spout, but do not turn the hot/cold handles on without the spout in place or you'll have a water fountain that will shoot to the ceiling. I picked up a 3/4 cap for the spout to prevent any accidents while I had the spout off.