Thanks.
Rather than an open plug, if I buy a second set of the current plugs, I can take a dremel with a router bit to them and just leave a more narrow pull handle allowing the mats funnel wall to countersink into the plug...possibly. The plug depression needs to be just a bit bigger than the mat’s funnel outer dimensions. HmmI got the plugs from @Jeeporama and trimmed the mat so it would lay flat and left the plug in the floor. My wife has Weather-tech mats and I like mine better, I think they fit better.
Gregj