Fairly sure the box is too long, so that would mean cutting chassis leg off/out.

If you downgrade to the ib5 box, you only have to change the flywheel/clutch assembly.

p.s make sure if your starter is at the back/front. It may cause your problems.
Where you at? I've a spare ka box, not been used in a few month but was removed from a working car. (unless you wanna sell the ka?)

EDIT, noticed your location.