Spent a few more hours on the shed and at this point ready for the final stage - roofing. From the last session secured the timber to the top of the back wall with stainless screws using the same pop rivet holes.
Lifting harness to assist her if needed going up the stairs and mitigate risk going down, in particular on her off days.
Already thinking of modifications cos I want the handle lower down closer to the back with my other hand free to hold onto the on the stair rail. Will also consider inserting a wood dowel inside the handle so I can apply more lift front or back. This one is $30 bucks and if it doesn't work out bin it try another one.