Can I trim a Thomas Dudley basin seal kit (Ed.)

[george121212]

Hi tried to use one of the Thomas Dudley basin seal kits. Fits great however a little thick and not enough thread left to screw the trap on.

Has anyone had any experience trimming down one of these basin seals, concern will be not cutting completely straight? Thanks

 

[polesapart]

One of these https://www.screwfix.com/p/mcalpine-s12a-f-1-1-4-bsp-eu-uk-coupler-white-32mm-x-32mm/4483v may help.

Upper female thread is shorter than male.