Your suggestion will be passed on. I believe there are two possibilities with respect to Grace Abounding. The Australia Rose Annual is incorrect having mixed up the names of Joyce Abounding and Amazing Grace or the attribution is incorrect and the rose referred to is a 1968 Harkness floribunda.
Well we would certain welcome his becoming a HelpMeFind member - it's free and completely private. We could then link his membership to his rose and breeder listings which would allow him to provide additional details or make changes at his convenience and interest. We're always particularity interested in breeder supplied photos.