If the head unit has the 2-wire resistive inputs you do not need an adapter for 04-06 FL1. My wife's car is an 05 3-door, and it programmed easily. Connect wire Key-1 to the steering wheel wire & isolate Key-2 with tape. Some head units might require Key-2 to be grounded. You can try both ways - it will not break anything.
Programming is the challenge, because different Chinese Android vendors vary. Some of them you select the function and then press the steering button
like this. On others
you hold the required steering button, and then select the function on head unit.