There is a "tool" (a 10cm long dowel)that screws into one of the wheel bolt holes - and it makes aligning up the wheel bolt holes.
Here in Germany... most tire shops will
only charge you ~35 euros to mount your summer/winter tires. You can also leave your "other" tires at the tire shop for a small fee too! This might be your best option.
Knowing how expensive things are in CH, that 35 euro fee could be more like 135 euros. Still it might be worth it to your back.
