Hello I own a LUKE II and have very less output signal. So I've checked the Pickup High and they are set at 5mm (I think it's 0.20 "), I would like to set them higher 2.4mm (~0.10"), but when i turn the screw nothing happens. I pull them out and saw that there's plastic shims undernearth.

My question is how schould i got to set them higher? Is there somewhere where i can find or buy higher shims?

I very novice with these subject, so please be easy on me