I have been looking at PSI cartridge pen kits, their instruction for both twist and click pen look easy. While like the PSI, click cartridge kits have not made one.
Do like Berea kits tad better. After getting, the flier went to web site to view instructions. There is a slight different in components but not difficult to make. Not sure how long Berea has been stocking these kits. Little surprised they did not have any on hand.
Guess big factor that got my attention is Parker style refills these kits take. Like the idea of not having to round up pieces, parts to put a pen together. Have not had a weapon since retiring from biggest & best gun club several years ago.