Hello Catrike owners!

I just bought a Villager, and with the crazy hills around here, I won't get far
on the single chainring. I want to fit a boom with a derailleur post and a
triple chainring, but I have no idea what components I need, or how to ensure
that all the bits are compatible.

Here what I do know: I want a 24-tooth granny gear and a 48 tooth big ring.

Please advise.

With thanks,

Gordon
Alberta Canada