If you have time and want to do a little more thorough job, find the spot welds on the strut plate and drill them out. The big plate will fall off and you will be able to work directly with the rusted metal. Align the plate back up and weld the holes up where you drilled out.
My driver side was ****ed so I had to give it new metal behind the plate, my passenger side was way better off so it got patched. Just a few pics for the driver side I did last year
112fe2adb7ed17bedbce882b0d29f80f by smetters20, on Flickr
7c076258cef436156fc7cb59f3a52175 by smetters20, on Flickr
8866061c2fe13a0b28bc5874d249e804 by smetters20, on Flickr
f6ba by smetters20, on Flickr
7d5195562aaf46067fabb52a7bf321ad by smetters20, on Flickr
