It's possible...but will likely require an external breadboard or the like to facilitate it. Basically, you would jumper all the components to a breadboard and set it up to switch between the two different values for each component. So, jumpers for 4 transistors, 2 diodes, and 1 capacitor. It's doable...but does require a bit of config.
Now that you said it...I'm curious how I could mod my own Ungula with this kind of mod.
I've only got three pedals under my belt so this would be beyond me. It's just a few components so I thought it might not be too difficult. Might be an idea for a new board "ungula plus"