Product review (5 stars): Elements are interchangeable.
Unfortunately I didn't open the heater plenum to make sure I was getting the proper mounting bracket for the heating element.  However I removed the old spring element and installed the new spring element on the old mounting bracket very easily.  New element works as well as the old one did (when it was operable).  So don't automatically send it back if you realize you ordered the wrong bracket.  Elements are interchangeable!