There is a lot of differences in the fronts.. ..but backing up front the nose...it gets smarter... the bonnets are all the same profile outline as are inner guards and more.
In 1972-73 front bumpers, supports & absorbers changed to accommodate the low impact collison laws introduced.
Overall..Engineers made a pretty easy & adaptable designed GM car to work with through a decade that went from full on performance to safety to the intro of tougher emission standards coupled with the Arab Oil Embargo.
70-81 Camaro Front End PDF