The interior in question I forgot to add is a 69 cutlass convertable. the rear seat springs are super bouncy, is bracing every added inthe seat to reduce the bounce, it's almost like sitting on a trampoline. BTW, I did read your tutorial about replacing the spring on a 70 cutlass seat.
here are a few pics of my lambo interior I did, I don't have pics of the cutlass seat I'm working on but I will try and post some today.
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