yeah ok, thats just the spray stuff you get at autozone, pepboys ect.
you could just use that but it will be waaaay off scale.
soooo........ what you'd probably want to do to make it more to scale would be to paint your trunk area with that dark grey first.
the easiest way of doing that would probably be to get a can of the dupli-color primer from autozone. they have a new color called "Gray Hot Rod Primer" it's # DAP 1692
it is a dark grey almost charcoal primer.
once that's dry, take you a cheap paintbrush or and old one or whatever and trim off a bunch of the bristles so you only have a few scattered ones here and there rather than a bunch together.
then take you a bottle of flat white and flat light grey testors......
shake them up really good.
take one of the colors and lightly dip the brush in the lid so you dont get much paint at all then lightly dap the tips of the bristles around in the trunk to simulate the splatters.
then do the same with the other color and there you have it
