I had one like that on my showroom floor many years ago - before HS started making lifts.
I had it set up just like you have, but with the base even farther away from the tub than you do.
It was a bit of work to open the cover, but I had it in our 'mood room' and I wanted to be able to walk around all four sides of the tub with the cover on the lift. It worked great for what I needed - I would open the lid first thing in the morning on Fridays and Saturdays and leave it open all day. Other days of the week I would play it by ear and open as needed.
Good job.
8-)