SpringFree Trampoline Shifting Frame (DIY Version)

I have a 13 x13 SpringFree Trampoline that I need to move occasionally by myself. SpringFree shifting frame and wheels are $100 (each? https://www.springfreetrampoline.com/products/black-shifting-wheels?srsltid=AfmBOoqLvLjwa5BLoFSWBzUVaudCHz3vD-RRAXB8zP8h9DP9-KmgGkWL) so I decided to learn Fusion360 and create my own. This frame is designed to be used with 8 in Harbor Freight Solid Rubber Tires. I designed my own wheels but never tested/printed them because the model would have taken longer than I wanted to print….and I needed an excuse to go to my local HF store. The tires have a removable plastic hub where the axel is secured using a small cotter pin. I also purchased various washers to remove some of the play because the tire axel bore is larger than the frame axel. I didn't redesign it (yet) because it's been working fine. BOM:HB Tires:8 in. Solid Rubber Tire with Polyethylene Hub:https://www.harborfreight.com/8-in-solid-rubber-tire-with-polyethylene-hub-61706.htmlCotter Pi