Hello I am the happy owner of a Custom Shop Precision Pro Classic Closet from 2011. I looked under the pickguard to adjust the Truss Rod and I saw that there was a metal plate (seems to be aluminium) under it, with the exact shape of the pickguard abnd it's sandwiched with the pots. There were traces of oxidation on this plate (white powder). I wonder what are the advantages of this design vs. shielding tape (alu or copper) sticked to the pickguard's back... Moreover the general shielding is looking poor as there is only a copper plate under the pickups but nothing (bare wood) in the pots cavity and nothing on the sides of the pickup's cavities. Time for a shielding job or "don't touch it" because it's a custom shop and it will impact negatively its value ?