I recently bought a piece of 3/8" x 2" flat stock from the local Napa/farm supply store to make new front shackles for my K20. I only plan on going 1/2" to 1" longer to keep the spring from hitting the frame. My friend says that the factory shackles are hardened steel and are way stronger than the 3/8" that I bought, and that the 3/8" will bend real easy, easier than factory stuff. Questions: Are the factory shackles hardened steel? Which is stronger, factory or the 3/8 x 2 flat stock that I bought?