Conn came close to lifting the heavyweight crown from Joe Louis in 1941. Which light heavyweight would you put in Conn's place to beat Louis? Matthew Saad Muhammad, James Scott, Donny Lalonde?
Its funny I think Conns overrated at 175 and put quite a few LHWs from the early 20th century above him. But almost none of those LHWs I'd expect to "finish what Billy Conn started".
None could really came close,but maybe Archie Moore or Ezzard Charles in their primes could pull off a nice fight.