"from toe to heel in mm: 6.72, 6.67, 6.59, 6.54, 6.56, and 6.66."

Simple fix:

6.72= one layer of tape
6.67= two layers of tape
6.66= three layers but the third one sliced in half
6.59= four layers of tape
6.56= five layers of tape
6.54= six layers of tape

Then add a layer over all those different taped sections, and you're all set!

You can strop with the same set-up and you might benefit from shaving with the tape on as well.

Make sure to make a note of at what point on the spine how many levels of tape were used.

Piece of cake!