Finally got her...
Took me 8 restarts (got creamed a few of those times) with different torp depth, spread angles and so on to put her to rest.
set at 800yrds
2torps at 9f
2torps at 10f
spread angle from 2 to 0
Yes I cheated with this career.
As the Ise didn't sink after 36hr at the first go (which in my opinion should have happend) I cheated death on this one.