New Trooper here, those #2 Exacto knives are amazing for trimming down the armor, I started out using Aviation sheers, the thought being that the Exacto wouldn't be able to cut through the ABS, but after scoring the line a couple times, the pieces snap off like a dream.
Also, I saved the strips that I cut off to make snap plates and interior shims, saved me a little time, and let me use my nice clean ABS sheets to make those pretty cover strips/exterior shims.
Do not underestimate the power of a nail file. I've been using the round edge of those cardboard nail files, the fine side, to buff out some scratches that inevitably occurred, specifally on my ear caps and shoulder straps. I've actually not used a single piece of sand paper yet, period.
Just offering some insights from the building experience as I go through it for the first time.
