There is still something not right here. Something you are not telling us lol.
Look ... I am far from great on music theory, but I was able to use that book Jazzology straight away in a practical sense to play through the theory and the examples the book discusses, even though they never mention guitar in the book and the examples are written there for piano.
Since you obviously know a great deal more theory than I do, and are vastly better at sight reading, it does not make sense when you say
" I cannot relate anything in these harmony books to guitar or apply it " ... something just does not add up there.
You say
" I want to be doing more on the guitar than reading theory ". OK, fine. Well why not just do exactly that? Just start practicing like crazy on everything you can get your hands on that is related to the style of music you want to play!
Also re Jazzology, and when you say
" You guys are punting Jazzology, so I'll try get hold of it as soon as possible ", that book is fine for me, but it sounds as if it will be way below your current standard. I would not bother with books like that if you already know much beyond basic theory ... especially if you don't want to take their piano examples to play on guitar.
Why is a music degree out of the question? If you want to do it, then you'll just do it ... that's the way a first degree and then PhD work, ie - people who end up doing a PhD and post Doc and then research, are the ones who won't take "No" for answer ... you just do whatever it takes.
I wish I could advise you, really! But it sounds like you are self-defeating by default in your approach to what you want to achieve.