These NASTY tar-like black patches inside the seatbelt retractor slots??

[fixizin]

WTHey they be for?... sound-damping to prevent the rapidly retracting belt from slapping the sheet metal of the B-pillar?... err whut?

After 22 years of Vegas heat, Phoenix heat, and So-Fla heat, the one on the driver's side let go, and the adhesive on the backside stained the shyt out of the belt fabric. (Cleaning tips appreciated.)

As you can see they're 4" wide and 4.5" tall, a semi-shiny black tape that's smooth on one side and gooey-sticky road-tar on the other. I definitely want to pre-emptively remove the pax-side patch... hopefully not crazy involved... too many other things to get after.

 

[fixizin]

Turns out it's covering an almost 1" diameter HOLE that's probably inherent to the metal-stamping and/or robotic assembly process...


Here's the EXTended cab seatbelt, Driver Side, minding its own biz... note the notch for the Mazda cargo cover--a window-shade type device never to be found, anywhere, at any price!

Here's a close-up of the cavity, including hole formerly covered by tar-patch...

>>>WELCOME any ideas of what to PLUG IT WITH, thanks in advance.