Tinting clear parts

Future Floor polish and some brown water soluble ink. Could also blend some food color for the brown if you can't make it to the art supply store.

Hit the LHS and pick up some clear paints from either Tamiya or Gunze, that's how I do it.

A cheaper and better rout is to go to Hobby Lobby or any craft store and by one of those kids suncatcher kits or the stained glass window kits,, they come with about 6-8 tubs of tinted colors used to paint the kits with and work great for tinting canopies or marker lites as well as formation lites.

Coffee brown?
Mix a few drops of coffee in Future and dip the clear parts