Reikel wire stripper slider

I've bought a cheapo wire stripper from Tesco. After unpacking I've noticed, that the lever of the spring is just sliding on the inside of the plastic handle, which already leaved a mark and also caused a jerky motion. To mitigate the wear on the handle, I've quicky designed a slider that fits between the inner side of the handle and the lever. As I put it in place, the slider started making some squeaky noises, so I applied a little bit of grease. Step file is also provided.