I bought this 1999 SG Supreme with P-90s. I took the cavity control cover off first and found this. Then, I pulled the P-90s to have a look at the back of them. Nowhere does it say "Gibson". Are these correct for this guitar? I figured the part glued to the control cavity plate is the stack for the neck pickup to make it hum cancelling. The bridge pickup is stacked under the bridge pickup. What do you guys think?