From TheSamba :
I just did this two weeks ago, but it was to replace them...

1) Buy new ones. They are really cheap.
http://www.busdepot.com/details.jsp?partnumber=211955993
2) With a big pair of vicegrips, grab a hold of them and slowly pull
them out by wiggling and bending. They will be ruined once you get
them out.
3) Switch them.
4) Keep toothpicks in the kitchen.

Be extra careful not to scratch the paint. Be extra careful not to
drop the hose into the hole, you'll need to remove the dash to get
them out.

I used a heat gun to heat up the tips of the hoses in order to swap
nozzles, since the hoses were hard and stiff.
(credit McVanagon)

More from The Samba :

Grabbing them with the mini vice grips is the right idea. Put some
duct tape on your paint before you pull on them in case the
pliers/grips slip off them in the process. Turn a quarter of a turn
and pull. If you have a hemostat, clip the hose and leave the hemostat
on till you are done. This keeps the tube from slipping back in while
you are putting the new ones on. This is a MAJOR pain if it happens
(Credit hilllaguna)

Good luck,
Miguel