I love this holder, but have a pathological aversion to Heat Shrink tubing! I always (ALWAYS) forget it when making splices (and often in other situations).
So, I added the "Heat Shrink !" text to the floor of this excellent Solder Fingers model.
Thank you, MisterTech, for the starting point!
Fusion 360 Changes
Imported Mesh to get the STL file
Must turn off Change tracking
In "Patch" view, converted to Body
Merge faces as needed (I did the vertical sides & the floor)
Then, create a sketch, add text and extrude