Those little 90° grinders are awesome. That's a good purchase you won't regret any time soon! As for your rust problems, what you could do is take some sheet metal and put the 90° brake in it, then if you have access to one, a metal shrinker/stretcher on the bent lip will be able to produce the same rounded shape. That is what I did with mine where I cut out and reshaped the fan blower area. Good luck on the repairs! I know you will get them right
