But you need a bleed resistor from battery + to the body
And most likely also add a capacitor on the to change the modes normally
SMD resistors and capacitors can be recycled from from old electronic parts
I am from Germany and was also thinking to get the modification, but its not so easy and I really dont need a lighted tailcap as they have quite high parasitic drain
And on a SS tailcap you cant just unscrew a bit for lockout like on a anodised light