I dunno, lap belts tied to the seat are the simplest option people generally do. It all comes down to how and where they anchor. What kind if tensile load the attachment points can take on the belt to frame and frame to cab seat pan. If I remember right, the frame mounts to the slide rails with 1/4" bolts, that when stock, are not all that high of grade likely and the metal tab's strength itself. If you want to go this option, I'd beef up all those or all you'll do is tear the seat off the pan and not really do much else.