yes, I mean the front loader. I have a bad habit of calling everything a bucket. Thanks for your comments.I've never seen forks on a backhoe bucket. Do you mean on the loader bucket? A 455 should have both a backhoe and a front end loader.
I have clamp on forks that I use on the loaders on both my Ford 4000 and Kubota BX25D. The forks move the weight farther forward than a load of dirt or stone in the bucket, and so it limits how much weight you can lift with them. I haven't had any problems with either bucket n terms of bending or deforming.
If you are concerned with it though, they make clamp-on forks that also have chains that go around the bucket so that the top and bottom of the bucket both bear some of the weight:
forks with chains and binders