Hi Gary,
What I did was glue the track down and then when the glue is dry, take a NT cutter with a sharp blade and trim the cork overlap level with the ends of the ties, and use a wood chisel to scrape away the trimmed edge. It makes for a little more ballast being used, but allows the profile of the ballast to be taken up right to the side of the track, allowing the end of the ties to still be visible after ballasting and IMHO, looks cleaner and more prototypical.
Take care when trimming the cork that you do not trim the ends of the ties.
Cheers,
Steve