Chris Adams writes...

I am most familiar with Jim Harper from Roger Stern's novelisation of THE DEATH AND LIFE OF SUPERMAN, which includes some musing from Jim on his original career as the Guardian back in the Forties, his Newsboy Legion buddies who grew up to found Cadmus Laboratories, and their gift of a new cloned body for him so he could be a young, healthy Guardian again.

Given that the modern-day Guardian believed himself to be the original Jim Harper's grandson, and Roy Harper's uncle, that's obviously not his story!

Separately, you have confirmed that the Light founded the Cadmus Project, rather than taking over an existing institution.

Does any remnant of the idea that the Newsboy Legion grew up to work at Cadmus remain in Earth-16, even if they didn't found it?

I would guess not, given that it's unlikely the Light would have been organised long enough ago to have founded Cadmus when a group of men born in the Thirties would have still been active in the sciences.

(Plus, maybe it's a touch unbelievable that all of the Newsboy Legion kids would grow up to pursue the specific scientific interests necessary to be useful in a genetics company!)