All,
I am not trying to badmouth these companies that offer Mustang II's but I want to make all aware that there have been some catastrophic failures with them. The top spring perch of some of these has failed, meaning the spring itself has pushed right through the perch, causing complete suspension failure.
There are some message threads about this, even here on stovebolt. I do remember another member here (dakota something or other) who offers a kit which is much more heavy duty steel, but he also wrote up his recommendations on fortifying the spring perch (involved welding some additional steel washers/plates on top).
Again, not trying to bad mouth, and the debate will always rage on as to whether to clip it or Mustang it, but just wanted to make some of you aware of what can happen. Please have an experienced chassis builder review your set up before you paint/reassemble.