77-78 bumpers

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=6187&item=2429937703

a 76 280z as seen by the title and the front bumper. But the seller has a 77/78 rear bumper on the car (bumper guards) Do the 77/78 bumpers bolt on to the 76 chassis, and if so will the front bumper work? Im trying to find a way I can replace the bumper guards for my 76 but they are hard to find and expensive.