sorry for bad quality pictures
Step 1: The Base
Step 2: The Middle
the middle has two components almost the same.
Step 3: The Top
Step 4: Connect
connect the three parts
Step 5: Pushers
the pushers is the main part of the door lift.
the pushers work from both sides, the side where the motor is, and the other side.
Step 6: Connect the Pushers
connect the pushers with this thing.
Step 7: Gears and Motor
this is the part where the motor drives the door lift.
Step 8: Congratulations!
you just finished the door lift. have fun!
i hope it was clear enough.