Corsa-e electric Offside driveshaft removal

[lsc4alm]

Hello forum,
Had our used 2021 Corsa-e for a few weeks now but unfortunately I need to change the offside driveshaft due to a previous poor boot repair with cable ties.
Managed to source a recon driveshaft to carry it out DIY.
Not too bad a project for the outer section but we just can't shift the inner section that connects to the reduction gearbox/diff. It's otherwise loose off of all the brackets.
Just wondered if anyone else had come across this at all and knew if there was any sort of retention clip used in the box?
Very little info online, could only download a workshop manual for the e-corsa rally version that seems to indicate it should come out fairly easily (unless it is slightly different design of course).
Got a horizontal hammer type tool coming to try but grateful for any further ideas / advice.

Thanks.