Errant light spilling into inserts from nearby bulbs can be annoying & distracting.  3D-printed LightShields reduce the effect — install at a nearby screw under the playfield!  The base includes two holes for optional fit/positioning, and the shield itself is thin enough to trim off material to provide clearance if necessary.  LightShield color may vary but will always be neutral (e.g., gray or black).  Sold in packs of 10 for $10.