In Japan, there was a low profile chin spoiler (still available) attached to most front bumper assemblies. I've seen some up here in Vancouver, somebody like Erubuni (?) makes them, but they look stock (different than some of the body-kit front-end ones). 

Here's some dusty pics of the modifications I've made to my front bumper:

The chin piece in the pics is from an old school CRX found at a junk yard. It originally came as two side sections and one long front section. All three pieces required some modifications to make them longer. Plastic body filler and thin sheets of metal 'stretched' the chin into one long piece, plus lots of sanding, re-sanding, and primer spray. Top coat was PPG blue-green metallic.

Compare the USDM version to the 'CA' (Civic/Accord) front end at Redshift Racing. Same bumper as the USDM version, but the front turn signals have modifications for city lights. Obviously, the driving lights are different on the CA version. Seems similar to the USDM Honda Civic.

Can barely see the Honda optional antenae extending from the left bumper corner. The top is meant to glow with the letters 'H-O-N-D-A'.

Preparing the surface to take the paint takes time and patience. Fill any large holes (if necessary) with plastic body filler. This special filler adheres to plastic surfaces extremely well. Mix catalyst and filler as instructions indicate. Cheesegrate file the filler down and let dry.

Smooth out the surface using progressively finer grits of sandpaper. Block sanding (long and short block) will make the process easier and more even.

Keep checking for imperfections, sand as appropriate. When as smooth as possible, spray with primer, and let dry for at least one day.

Use spot putty (Ditzler Red Cap DFL-17) to cover the remaining imperfections (if any), and re-sand. You may want to wet-sand providing you have a fine-enough grit paper. Re-spray again with primer.

Clean in between steps with a wax remover (Acryli-Clean Wax and Grease Remover). Mask-off the parts you don't want sprayed.

The most important aspect with respect to painting is obviously chosing the correct colour to match. PPG blue-green metallic was used. 

Painting Engine Bay

Essentially the same preperation process as for the bumper, but no plastic filler used. Go heavy with the de-greaser, engine grease will not allow the paint to adhere as well. Masking is also important, especially if you want a clean look with minimal overspray.