I've been wanting to add cup holders, and didn't want any of the cheesy plastic aftermarket options that are out there. This was my solution: Purchased stainless boat cup holders on Amazon. These were maybe 25-30 bucks for both. There are smaller (and cheaper) versions that would be a little less intrusive, but I wanted to be able to carry around a 32 oz insulated tumbler. I welded the cup holders to a 1x1 square tube. Drilled a hole in the floor and used a Riv-nut. Hopefully the single 1/4 bolt can handle the weight, I wanted to use two, but the trans hump isn't flat enough.