backup the cfgs, recompile and move the cfg files back in.
you wil not need to "make install-config"
As long as you didn't modify the installation with stykesheets or else you'll get it working quite fast. It's usually only ./configure -> make -> make install.
In the src directory of your old install you'll find a configure.log file.. in the first lines you should find the configure options you used compiling your present install, better use the same options so you don't need to change anything in your setup.