Control arm bushing

[Humdong]

Hi. I am newbie looking for some advice. We recently picked up a 2005 H2 with low miles - but hard (offroad) miles. We have been working the bugs out. Finally found the front end noise to be loose lower control arm mounting bolts. They have probably been loose for a while as they have rounded out the holes in the frame and now their is about 3/16" of slop in the hole. Ideas on how to fix. My idea is to weld some thick washers to the frame in the correct locations. Good or bad idea - and any other suggestions? Thanks.