First and foremost, thanks to Fairymoth for the V6 model. I found it was almost a perfect fit but needed some adjustment, so I sliced it up with 3D Builder and made some adjustments so it would fit my spring (slightly wider) and added 2mm thickness to it so it was a closer fit to my DC28's part.

Notes on printing: There's some wiggle room but you should try to make sure it prints out the main part 16mm wide (excluding the pins). In Cura with my printer I had to set the horizontal adjustment to -0.1mm because it was printing out 16.1mm wide causing things to be a little too snug.

I recommend printing it vertically such that the part you press with your thumb is at top, using tree supports. If your slicer doesn't do a good job with the supports rotate it to 88 degrees so there's more room for the branches to work with.