[Clfs-support] re-using a toolchain question

[bvl]

Greetings

I have just built clfs (amd64) and I want to to upgrade to the latest gcc but 
I do not want to start at the beginning.  I want to reuse the toolchain (stuff 
in /tools and /cross-tools).

However the linker has been adjusted to point to /lib 
( section 10.8 of the clfs book here:-
http://cross-lfs.org/view/svn/x86_64-64/final-system/adjusting.html )
and I want it to use the one in /tools

My  knowledge of perl in zilch
and I am not confident enough with sed  
to reverse the script shown in section 10.8

 so I would be grateful if someone more expert could provide a sed ( or perl 
script )  that   readjusts   the linker to use the one in the toolchain.

Thanks in advance
sincerely
bv