I need to swap the cables over..thought I’d eventually get used to having the back brake on the left but alas..no. had a few close calls grabbing the front when wanting the rear..

Follow this guide but just swap the levers…
click me

Undo hoses
Change them over
Tighten up.

It really is that easy!
I’ve done it literally dozens of times. Never needed to bleed one once. 🙂

Before re-connecting hoses you can apply very gentle pressure between the pistons/pads to get a bead of fluid on the end of the hose fitting, this reduces the chance of getting air in the lines. Very gentle mind you, no point squirting 20ml across the floor 🙂

^^ on a related note, I need to replace a lever – can I just undo hose and attach to new one or do I need a new olive ?

Just a straight swap, no new parts needed. The Olive is the part that makes the seal.

Thanks

Carefully unscrew the hose at both brake levers and swap them over. Done carefully it is very unlikely you will need to bleed the brakes afterwards.

Thanks.