piece of cake bro, replace all thew bad line and bleed the system down......
try to use 1 piece lines that are already flared with the flare nuts
installed, if it's too long just carefully bend a loop in it
and shorten it up.....christ sakes man,
i plumbed half my direct port nitrous system using replacement brake lines
from NAPA !

You can buy an inexpensive small dia tubing bender but you can't use a
regular flare tool.  The flare needs to be double, or folded over.  takes a
special tool which is expensive.
LD

--------

Any kind of lines are a major pain in the a.s, but with the right tools
(DOUBLE flare tool, good pipe cuter, and bender), all it takes is time.
Lines are super cheap... buy more then you'll need.. your bound
to mess some bends up (everyone does).

HDS

NAPA sells replacement lines already flared and for real cheap.  Just
make sure you take an old fitting with you and have them match it up.
They also sell a union to join together two shorter lengths to make a
longer one (you may not need these for your application).  These lines
are soft and will bend with only your hands as long as you are careful
not to kink it and make a nice long, slow bend.  You can even put a
loop in a long piece to shorten it up with only your hands and not
special tools.
A set of tube wrenches will be real handy.  The old fittings may only
come out with vice grips and they may not spin on the old tube so you
may have to cut it and then take the fitting out.  If things are that
bad you may find that the bleeder nipples are seized (that is another
story).
--
Regards
Gordie