Hi Tony,
well me also owning a Sov GT well two of them, I also struggled with the tones, and to be honest still do, but slowly getting to understand what the GT is saying.... Dont give up hope yet, Yes it can be hard work and frustrating when you see others finding items as soon as they step into a field

but remember to sweep slow and keep it low, listen to the changes in tones and dig them all until to begin to associate the finds with the tones...
As for pinpointing when you have switched to pp mode in all metal slow right down with your sweep and you will hear the tone loudest when is almost above the find, place coil on the ground lightly then tease forward and backwards and listen for when the tone gets louder and where you located the loudest tone last time it should be centre of the find, depending on the coil you are using will determine if is dead centre of the coil or just in front of the coil bracket / support.....
Dont give up and happy hunting