[nass]

for the hood, get it photoshoped first to see what it's like. If you like it I would just use vinyl inside of paint.

Grill, yeah I'd do the mesh part a darker accenting colour. In your case a gunmetal colour.

Headlights, it's easier than you think to crack them open. All you need is a hairdryer a flat tool/device ( butter knife works well in a pinch ) and some small wood wedges or something along those lines. Heat up the glue at the top, pry it open a bit. Put in a wooden wedge or equivelent so it doesn't re glue itself. Repeat this until the the light can be pryed apart totally. If you take your time and won't go all HULK on it you'll be fine. I cracked open a few head headlights with no issues you just use common sense on when you can apply force or not.

Painting the inside I would highly recommend some light sanding, high adhesive primer, and light coats of paint. Take the time to paint it properly cause it shows in the end.