On the other hand - to answer the question!!!!
It has been done (not by me!). The front trunk support (or some such name) needs to be replaced too. It is a good opportunity to change to fibreglass front and rear bumpers if weight saving is your bag. Jens Wendorf did it, as did one of the R-Gruppe guys (not one who posts here though, but one of the other guys posted a pic once).
http://www.pelicanparts.com/cgi-bin/vb/showthread.php?s=&threadid=9183
That is all I can find.