I welded mine on, but I put on a reinforcement pad first. Atwoods had some 1/4" thick plates designed for bolting flat springs onto trailer axles and they were just the right size for my P 7010 bucket (about 3 x 5 ) I welded them solid all around then plug welded the holes in the plate into the FEL top, then welded on the hooks. I just put them on each side in line with the cylinder attachment points. I have seen too many bent buckets in the middle from folks picking from the center. Before I would put one in the center, I would have to put some angle or channel across the top for stiffening first.
I have used my FEL hooks to lift the front of my 1500 Chevy 4 wd truck which was about all my FEL would lift and had no damage or bending. I figured that was over 3000 lbs and maybe lots more since most of the weight of the truck is in the front.