Option #2

Constructed the Laddervator frame using Option #2 (flanged wheels on the outside of the frame). For wheels I used 2.5" Campbell pulleys (4x). They are rated to support 550 pounds - much more than the max 200 lbs I'm planning for the prototype. Everything bolted together very smoothly. I used some old shelving brackets that I found in the as well as remnant shelf-supports and a couple of linear feet of azek. I drilled a hole at the top of the frame through which slipped a caribena for connecting the frame to the winch. Construction time was a couple of hours.

Here's a picture of the prototype Laddervator frame in place on the ladder. You can also see the winch (orange box at the back of the ladder). More about that later!