As long as the borders are the wild west ANY amnesty will produce another (bigger) tsunami of illegals.
The guest worker program I envision would be exactly what the name says.....a "GUEST" worker problem.
If an illegal immigrant wants to "upgrade" to legal status, he could apply for a guest worker permit but "amnesty" would not mean a Green Card. It would only mean he was now a legal "guest" for the time period specified.
At U.S. Naval Base, Guantanamo, we had Jamaican "guest workers". They did the jobs we needed done, they got paid and, when their contract period was over, they either signed up again or they went back home to Jamiaca.