And another question I am thinking about since a few days.

I have an old lightrail a friend gave me. I think a photo could make this easier, just watch:

Attachment 297094

Do you think it's worth to use the light rail for this small movement ?

Do you noticed the small red circles ? Just want to show u the coolest lamp holders ;-)
They're called "Easy Rolls" - about ten dollars - every penny worth ;-)

(No Commercial, No Links, just a hint ;-) )