Getting xorg-7.4 from git ?

[Pavel Troller]

Hi!
  I would like to ask, whether it is possible to get a 7.4 release sources
from a set of modules, downloaded with a standard git_xorg script. I don't
want to download all the modules again, I would like to make a local copy
of the whole x.org source directory and then apply some "magic" on one of
them, to change from master branches to the particular tags, required for
every module. My knowledge of git is just a very basic, I don't know even
a command, which does this for a single package; otherwise, I would be able
to write a script doing it using the list of modules myself.
  Any hint would be very appreciated.
    With regards, Pavel Troller