Pulling fork on disc brake bike

[deluz]

I need to remove the fork on my Tarmac to trim 5mm off the steerer tube.
I am thinking that I need to disconnect the hydraulic hose at the shifter and unwrap the bar tape. I am assuming I need to plug the port in the shifter to keep the hydraulic fluid from leaking out and bleed the brakes after re-attaching the hose. Can the olive be reused or do I need a new one.
Thanks for any advise.