Here's a kit to add rear wheels and higher handle. I was reading about it in Farm Show magazine.
https://shopspur.com/product/tri-will-burrow-retrofit-kit/
https://shopspur.com/product/tri-will-burrow-retrofit-kit/
Wow, impressive! (you did marry good!) I would have brought a material conveyor from a mine to move that much material!I have my dad's smaller gardening wheelbarrow I used to landscape our yard in Illinois in High School. I changed the wheel on it but as I get older, I find its just the right size to get into tight places the FEL won't fit in... Like my living room. (Did I marry good or what?)
This was the first project I bought my Kubota for... getting 27,000 lbs of tile shards into a dumpster.