[jakeru]

Glad to help! Not sure I can help much on the filling, but on the small indentation, polyurethane can be worked (especially back to its as-molded shape) by applying decent amout of heat and also just a small bit of pressure can help.

I took a bumper that someone else had butchered up "modifying" it to install an incorrectly fitting lower valence piece, which had been stretched it in in pretty unsightly ways, and also screwed with a few dozen various types of screw, and I managed t0 basically complete undo all the stretching, and even unpuckered and substantially closed back up all those screw holes by simply working the bumper cover carefully with a heat gun and applying very light pressure to help speed the material movement by pressing against it with the blunt handle of a screwdriver.

If you try this to undo the small pucker, it might help to first remove the bumper cover so you can press from the backside. Also, go very slow with the heat as you don't want to burn the paint! This didn't happen on the bumper I worked, but I notice that sometimes when it got quite hot, sometimes, it almost looked like the clearcoat temporarily delaminated, almost like a small, temporary blister - but it seemed to go back.

I think the clearcoat itself of this particular bumper was actually polyurethane also. Not sure if Porsche front bumpers have polyurethane clearcoat. The rear aerokit 1 bumper on my boxster certainly doesn't have a polyurethane clearcoat, but other painted steel surfaces for the car definitely do. It's possible the aerokit 1 parts were finished separately and differently from the rest of the car.

That bumper I worked looked really great afterwards, especially after I put on a new, proper fitting lower valence on it, which luckily hid all those screw holes. I also touched up the rock chips with a quick drying, lacquer touch-up paint pen, which was easy to do and instantly made it look better from a few feet away.

Not sure what would be suitable for filling a hole in polyurethane. Your normal body fillers, like bondo, might not adhere well to the polyurethane, and might not be flexible enough. I think it's a difficult material to custom-modify, or even produce in small quantities, which is why you won't find many low-volume aftermarket bumper covers made out of it.

Some people fill their Porsche front bumper license plate holes with round, painted plugs.