Hey Steve! First off - as a general suggestion - make sure you're still practicing your scales - preferably with a metronome. A big part of this is drilling your picking and dexterity with single notes.

Beyond that, then it's always great to zoom in and isolated one or two bars of the lick you're having trouble with, slow it waaaay down, loop it, and drill it, making sure you're playing it slow enough that you can execute the lick correctly. Then, it's all about repetition to burn it all into your muscle memory and fingers -- speeding it up will be much easier after this process.

[br]It's tricky to get the upper frets to ring out since they're so narrow - you'll need to experiment and adjust the way your fingers fret the notes so that the notes ring out clearly. Beyond that, perhaps there's an issue with your guitar - maybe it needs a set up if it isn't fretting correctly?

Here's a tutorial to work on your speed and dexterity:

https://www.guitartricks.com/tutorial.php?input=1191

It has more of a shred focus - but the underlying approaches are sound.

Down On The Corner sounds like a great fit!! Dig in and let me know how it goes!!

Mike