No offense- but you be careful.

You want the easy to replace to part break first (weak link). And if it flexs a bit- that reduces load into the body. Beefing up the bracket, you may find a broken point on the body next time which will take welding and metal instead of R&R a bracket.

Early cars were thinner than later W124's. On my 94', the passenger side was broken.

Just go buy a replacement... make sure there is no sharp edges, the radius block under the bolt should be snug into the radius, a little MIL-8802 or something so there is no corrosion to initiate a crack.