The main challenge would be the difference in the front subframe. The 1969 Camaro has a unibody construction, while the 1977 Camaro has a separate frame. This means that the front subframe of the 1969 Camaro would need to be modified to fit onto the frame of the 1977 Camaro.
Additionally, the suspension, steering, and braking systems would all need to be modified or replaced to accommodate the 1969 Camaro front end. This would require a significant amount of fabrication work and would likely require custom-made parts.
Overall, it would be a complex and challenging project to put a 1969 Camaro front end on a 1977 Camaro, and it is not something that should be undertaken without a high level of skill and experience in automotive modification.