Is the huxley flexible enough to add a second extruder head? If so, what would I need in order to go about doing so. I'd like to be able to print in two colors if possible.

There's always a way to do anything if you want to work hard enough at it.

How much print area are you willing to give up to do this? That's always the first question when dual extruders come up.

Do you mind that one drips (oozes) a bit into the print? If so then you need a dual carriage dual extruder. (cool but complicated).

From what little I've seen, this isn't going to be a straight buy it and drop it in upgrade on your printer regardless of the direction you go.

I suspect a Bowden head dual extruder will fit in the space of the existing setup. That's not to say you *should* do that.