yes it can be done without removing the steering wheel , the plastic piece i think you are talking about is the top piece which just clips in, I have the complete instructions. as below hope this helps. took me about 30 mins
To remove the instrument cluster, proceed as follows:
Remove the 3 Torx screws on the lower steering wheel shroud, unclip the lower shroud from the top shroud and remove (it is made much easier by pulling the steering column fully out, and leaving the adjustment lever loose to be moved around whilst removing the shroud).
Remove the 2 Torx screws keeping the upper shroud on; they are high up towards the column stalks. Remove the shroud.
Remove the 2 Pozidrive screws securing the bottom of the instrument panel on. Remove the cloth trim that covers the gap when the steering column is at its extremist positions.
Remove the 2 Torx screws securing the top of the instrument cluster in place, on the lip of the dashboard.
Adjust the steering column so it is at its most out and lowest position; lock it in place.
Carefully pull the black trim "blade" at the top of the instrument cluster and use it to lever out the cluster; when you can, undo the connector at the back by pushing in the tab and pushing the red lever to the other side.
Manoeuvre the instrument cluster away from the dash, paying particular attention to the bottom lugs and the wiring on the steering column.
