WOW, what a GREAT batch of info! THANKS for showing the videos.
I think you have made my life a bit easier with this info.
I think I will offload our dedicated mat in favor of a blue tarp. I always keep a couple of small ones aboard any way. It was great to see how well it worked.
My new plan will be to use that tarp as step one. Then use the Splash Guard on the inside as step 2.