Here are some pictures of how I mounted the AF1 and an audio amplifier in a small case

The AF1 front view

Here is the inside view. I removed the rotary switch from the board to allow for a larger knob and to balance the front panel. The output of the board goes the phone jack and to the audio amplifier input.

I used a small audio amplifier kit for the audio amplifier. The output connects to a terminal strip on the back for the speaker connection.