Which polarity position for capacitor in Fat Fuzz Factory?

[Philtre]

I'm experimenting with different capacitor values for the capacitor between Q1 and Q2 for a Fat Fuzz Factory.  But there seems to be a difference of opinion about which way to put the plus and negative sides of an electrolytic capacitor. Should the negative side attach to the collector of Q1?

This is C2 in this schematic:

[Philtre]

I measured the voltages across C2 and there is a greater voltage on the Q2 side. Therefore I think this should be the + side.