Gouging out all the cracks is one of those things that ended up being more labor intensive than I expected. In some places the cork tore out in chunks, and on a couple of the edges long strips peeled away. It didn't matter. I saved all the debris from the process and once all the cracks were dug out, I used it as rubble in the voids and in piles on the street. After all the rubble was in place and the glue set up, I used a filbert brush to paint the lines on the road with PVA.
Now all that remains of the road construction is the cratered section.