JV: I'm pretty sure that hole is/was for a lil'cable light that lit up the tray. If my fading memory serves, some guys on the ol'RF Bored did the non-smoke tray and even ran that cable light into their new tray.
This is from a few yrs ago "memory",
Maybe the newer Xs don't have the light but the hole for it is still there?
We have self cleaning pick up truck beds, here in hillbillyheaven:
everyone tosses all their trash back in the truck bed and it self cleans as one rumbles down the 2 lanes at 60. WTF?!
BR,md