Switch for Duplo train track - Locking Slider

Thanks for the fantastic Duplo Rail Track Switch this is derived from. I did the following mods:

1. Added notches to the slider so it stays firmly in position.
The original slider printed too lose and was 'sliding' around at the slightest bump. This remix is as a drop-in replacement for existing sliders - so switches can be 'upgraded' without having to print the base again.
2. 'Mirrored' the base, which puts the lever on the opposite side (for whatever reason...). It's a little more involved than mirroring so the track notches to align correctly.
The slider can just be mirrored without mods and the remaining parts are symmetrical.