Minecraft 1.12.2 build elevator?

Ma
3

How can I somehow get an elevator in 1.12.2 without using the observer piston method? So roughly like a Seelensand elevator (which is not yet possible, because the update for Seelensand elevators etc. Is only available from 1.13)

He

Here is a video but I don't know if it would be possible in 1.12.2

but why actually without an observer?

Ma

Because somehow the items duplicate and it destroys itself when I start it, haha

He

Lul xD