Hello Bernie,
As far as fingering is concerned, of course, you do not start with the thumb on any of the black keys. So, it all depends on. Start on F# or Gb for instance... It would require different fingering. I've seen very little music written in six sharps F# but rather Gb except Chorus of the Hebrew Slaves from the Opera Nabucco by Verdi. https://commons.wikimedia.org/wiki/File:Verdi_Nabucco_-_vocal_score_-_III_4_Chorus_of_Hebrew_Slaves_-_Va_pensiero.pdf


Anyway have you worked on Hanon before? It is in public domain. I'm sure you can find it easily on the net. #39 in the book has scales and arpeggios. You already play the keyboard, and I don't think you want to mess with any method books, but the scales and arpeggios can help keep your fingers nimble. If you still want to get into a method book, there is a good beginners' book; an old German method book called Beyer (in public domain, too).
Chris