About 20 or 30 years ago they came out.
I have mounted my share of enlarger lenses and have never found any of
the usual ones that will not readily mount in a D5. Turret or not. But
I am more than willing to learn anything.

Tell me whaic 50mm you want to mount?

FWIW The D5 is very similar to a D6 and the D6 came out before the D5.
And there was a D3 and D4.