I gotta second the recommendations against using rubberized undercoating. I stupidly sprayed this crap ALL over the
inside of the notch of my trunk, thinking it would dry solid (like a softer version of Rhino Lining) and I could just leave it as-is without using any carpet and such back there to save weight. Sprayed it on a typical 100* Arizona day. No dice. It rubbed off on EVERYTHING that touched it. Sticky, nasty, stinky crap.
I later scraped the majority of the stuff, cleaned the trunk up, and resprayed it with bedliner. Worked much better, doesn't rub off ... although there's a few spots I missed where the undercoating goop will still get some black poo on your hands when you're reaching under the far corners of the trunk.
I would SERIOUSLY recommend going with a bedliner like Duplicolor, or better yet Herculiner, as it will dry/cure much more thoroughly and not rub off onto everything. I had good luck with rolling Herculiner all over the exterior of an '87 Firebird Formula that I had - it even survived a 45 MPH collision with a Saturn SL1 driven by a stupid old snowbird ... although the frame and body panels, themselves, didn't fare so well...