Hi Chas,
came across a good book many years ago, basically for classical players. " Jazz Improvisation for the Classical Pianist" by Martan Mann".
It was way over my head at the time, but, I ended up lending it to my piano teacher , (she was a really good classical pianist). Anyway she was so impressed she ended up buying a copy for herself.

The idea of the book is try and bridge the world of the classical pianist with the world of the jazz improvisor.
After studying the book , a classical player should have the knowledge to create their own stylings and arrangements from a Fake Book and have the ability to start improvising.

With the bit of classical piano I did learn early on, knowing what a chord was, wasn't part of it. I was too old to bother going thru 5 to 6 years of classical piano lessons, plus playing classics didn't really appeal. I was a real Richard Clayderman fan, so I painstakingly learnt the sheet music note for note. I think back on how much easier it would have been if I'd understood chord construction, would have made learning a tune a lot quicker.
Eventually came across " Bill Irwins Magic Study Series for the Popular Pianist". First section was on chord construction. Second section was on rythms.3rd section covered R/H Harmony, Embellishments, Block Chords etc. Fourth section coverd fills, transposition & chord progressions.
Last but not least was complete section on just Diminished chords, which covered intro's modulations fills interludes & repeats.
Never quite worked my way thru the whole book, it got packed up along with all my piano books after I had to sell my little baby grand.
Kids left, downsized to a much smaller home.

Anyway, I've dug the book back out again, and realized that parts of it could be handy for my arranger playing.