"Behind where the starter was, just in front of the slave cylinder is a plug with a hex for a 10mm Allen key, undo this, then use an M6 bolt screwed into the end of the shaft behind where the plug was to pull out the shaft, this is essential to avoid damaging the clutch release system. "

Done this? From memory this is the snag a lot of people run into.

How do you remove a gearbox from a 99 subaru impreza wrx