Hi Colin,
It's all food for thought matey, trimming is the one task I don't like. I use a barrel timing tool.
Have used it in a pillar drill but it always used to burn or darken the end, which is something you don't want to do.
I started on the lathe in a chuck on the pen jaws and had the trimmer in another chuck and used that. But that's not a good way to do it too. I have thought about sanding but again I don't have a circular sander and I'd have to fabricate a jig to ensure squaring it off.
So I'm really in the same dilemma as you matey.
Will get there I the end though ;-)
Lance