Thank you everyone for their input. Our team used 80/20 sliders for our minibot deployment in 2011, and we swore them off after that. So I have tried to mock up a lift I think we could build image below:

Specs:
- Two stage Lift with the primary towers built out of 1x2 1/16 wall Aluminum
- Second stage uses 1x2 1/8th wall C stock
- First stage uses bearings in bearing blocks designed to be shimmed out in order to get a precise fit to control front to back motion and the side to side motion is controlled by Delrin slides riveted to the top of the towers and bottom of the first stage.
- The second Stage slides are milled Delrin inserts. These can be milled and sanded until they slides cleanly in a test piece of C channel.
- All of the gusset plates are .050 Aluminum sheet with 3/16 Rivets
- Top black brace is made of 1/4in plywood.
- Since this is a mock up the tower is not adequately braced, but for now im interested in critique of overall design.