Proper Care for Interior Parts

[hdman90]

Recently came upon a brand new floor mat for my truck, but it has been in the box so long that the folds are beginning to crack. Before I unfold it, should I soak it in water or cover in Vaseline? I would hate to damage it more by simply wanting to use it!
Also, I have a '67 radio delete plate (that I do not plan on using, but would like to keep in good shape) that has lost it's shine. I have tried waxing it, but that does not seem to do the trick. Does anyone know how to bring a good permanent shine back to old plastic?

Thanks!

[HIO Silver]

Warm it up before unfolding.

I'd glue a flexible matrix to the back to prevent tearing where it has dry-cracked.

Vaseline seems to be a good idea but using a lubricant or protectant requires that it be used consistently and forever.

[Ranchero50]

I used baby oil on my vinyl parts and I agree, put a backer on it. Mine is in pretty good shape and has carpet underneath for padding.