Kimber Kap installation

Kimber kaps have a black and a red lead. Does it matter to what part of the circuit the red lead is hooked versus the black lead?
No, it doesn't matter.
In a signal path application: the black lead is, "input", the red, "output." In a power supply: the red should be "+", the black, "ground." AuriCap, WonderCaps, etc are all coded alike.
Sorry: a correction- In a power supply: the red wire connects to the voltage(whether + OR -) and the black to ground. Further: In a speaker system crossover application- connect the red toward the "+" terminal on the drive unit.