Too bad you didn't post this last month. I just sold a project 68 firebird for cheap. It was a #'s matching 400, too.
If you haven't already, I recommend you post your want ad on (also check what's for sale):
http://firstgenfirebird.org/forums/u...ds_Wanted.html
http://www.pontiaczone.com/forum/forumdisplay.php?f=462
Good luck with your search!