Derek G4VWI has used a sub-miniature MIL spec rotary switch to switch between common, off/slow/fast as per the ND6T wiring diagram for the Kit Projects board.
A screened pre-made wiring loom helps ensure the exposed sections are kept nice and short. Derek suggests choosing good quality connecting wire and pre-soldering the pads before tacking on the leads for best results. He believes that this is by far the easiest AGC board design to fit.