building a thumb for my backhoe

I was wondering what would be the best steel to use for my thumb. I use my backhoe for everything you can imagine demolition. Clearing small lots etc... i was told.i would be good with 1/2" thick mild steel but to me that seems light for what i need it for, but at the same time i dont want something so heavy that install and removal would be damn near impossible what is every ones opinion on this. Also how thick should i make the pins

building a thumb for my backhoe