Remi did not say longer screws.
The fin bolt chart lists M6x 45mm and M6x60mm screws for the normal Deep Tuttle Fin root.
The M6x 100mm screws would seem to be far too long because the Deep Tuttle fin only extends
into the fin box approx. 18mm more deeply than the std, Tuttle fin root..
If the std. screws (for a Deep Tuttle fin) are M6 x 45mm and M6 x 60 it would seem that you would
need M6 x 60-65 mm and M6 x 75-80mm to fit a std.Tuttle fin root.