I've been trying to breed a shiny Roggenrola with perfect IVs, yesterday I managed to breed a shiny Joltik, so I've been able to hit my seed before.
The parents are a Ditto 31/31/31/31/31/27 and a Female Roggenrola 31/31/31/30/31/31, I've managed to find a seed of a perfect shiny Roggenrola...