Rip It

I recently had mine out and discovered several empty bulb holders missing ? Each not being used hole had a piece of round paper material glued over the hole. Looked factory to me, is this normal ?
I also did the Clark's thing to brighten my dash illumination. I made one exception...I used aluminium vent tape instead of foil taped over. I figure that type tape is designed for heating and ac ducts/vents in home attics so the glue should not become a "goooey mess". So far this worked great, plenty bright.
I just answered my question when I double checked Clark's pics it shows the paper.