Really good fit on the worker version of the caliburn
From reading notes from remixes of remixes the build is a bit complicated.
The pump grip and front block are from this thing:
Do not print the slug version if you want to use the side rails.
The side rails is this thing (note is the a remix that cuts it in half as my printer isn't bit enough)
You will 2x M5 10mm (rear) and 2x M5 20mm (front)
I think if I was printing it again I would invert the colours so the rail and pump grips are blue and side rails in white.
I noticed when using the metal plunger tube it doesn't catch very well, however using the original printed one It works fine.
I suggest if you want use the metal plunger file a bit of off of the pump grip so it can go back an extra 1-2mm