No none, off the shelf. As Roylerumble said the stock used a truck GM bushing. Building a new one would be easy like MaSnaka said. The only factor is size of the mounting bolt/bushing you go with. I got mine up on stands last night. i'll try and get some overall measurements in the next day or two depending on my schedule. i was personally was going to try either modifying a stock SN197 performance version like below, or a adjustable fox body like from MMR. Not sure yet which way. I have not done measurements yet, but I was leaning on trying to use Mustang rear springs (you can get weld on perches) vice the Vega or Chevette el crappo springs
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