If done correctly you can weld cast steel. But if I got it wrong it could break when under stress, not when I would want it to happen. On my backhoe the dipper stick is made of cast ductile metal. Cast into it is the warning not to weld it. While I like your rear rack for me I think it would obstruct the view. I can't tell for sure but it looks like your seat is closer to the ROPS than mine. Between that and me having the factory storage box requiring the shelf to be up higher or further back to access it. I did look into making something like it, maybe something I could remove, but came to the conclusion that I would block my view more than I would like. I guess is some ways it's good that every model is different than others but also bad when it comes to customizing. I kind of shelv the idea until your work inspired me (several others in the past got me to try to find something that works too).