decodeing vin number what engine was in my car

Just because your car came with a 6 doesn't always mean you'll need those mounts. Example is that then I got my car it says it came with a 6 but when I started working on it, the car had a v8 k member bolt in there already (my car didn't come with a motor). Basically id find out which k frame/motor your using first and go from there. But yes, the 5th digit "C" does mean a /6.