"I did a bit more research - I think the first person to put chord + at the beginning of the sequences was Corradi in a songbook printed in Venice in 1616. Other Venetian songbooks do as well I think Perhaps Venetians were especially religious."
"The earliest surviving - incomplete - table of alfabeto chords is found in the manuscript known as the Cancionero Bezon dating from 1599. This starts with A and does not include a symbol for the E minor chord although some of the chords are not…"
"I wish I knew as well. I wonder if earlier alfabeto systems started with the G major chord labeled "A," and as the system grew, they knew that the e-minor chord needed to be in proximity ti the G major chord, so they used a non alphabetic…"
"Thank you for this arrangment for the baroque guitar, I also play Turlough O'Carolan on the baroque guitar for exemple Miss Mac Dermot, Carolan Welcome, Magan Magan, the Queen dream.... I find that double string and campanella are fine…"
"Edward, here you can find the facsimile:
Forza d'Amore is in the second book page 219 and 220.
It's for luth and italian tablature but easy to adapt for baroque guitar.