I'm going to switch it back to the white pickguard for the classic ric look. I noticed on a YT video of someone shielding their ric that their white pickguard was not totally opaque, so after applying copper tape to the back of the pickguard, there was an only just noticable copper tinge to the pickguard when it was fitted. I wasn't sure whether this was a trick of the light or I was imagining it so I experimented with my own white pickguard and I was able to conform that the pickguard did show a copper tinge when the shielding is applied to the back.
To prevent the copper showing through it would be necessary to have an opaque layer between the pickguard and the copper tape. I have a roll of self-adhesive black vinyl which I guessed would work well for this as my 4003is Jetglo so I used a layer of this followed by a layer of copper tape. The black vinyI went to the edge of the pickguard, but the copper tape did not to ensure it isn't visible when looking at the edge of the pickguard.