I think it is a great idea for the rear. I was thinking of the same design with a round 3/16" or 1/4" thick plate with a hole in the middle. Do you guys really think the front is necessary though? Especially if you have a good progressive spring that never un seats. My poly springs are that way at least. The front seems to have a bigger hump in the spring pad and the bump stop on the top. Seems pretty secure.