While rebuilding the front suspension on the '49 I managed to snap off both new spring eye bolts that I had bought from Classic parts. They were like glass, barely more than snug and they shattered! Since I work in a machine shop I took the broken bolts to work and checked them for hardness, for reference I first checked a grade 8 bolt at 31 rockwell the broken bolts measured 59 rockwell! A quick call to Classic and they confirmed that a batch of incorrectly heat treated bolts were sold and as usual they made it good by promptly getting me a good set. The bad bolts were silver in color with a triangle on the head. If you bought some recently it would be a good idea to call and check if they are part of the bad batch.
The new bolts are a dull iron color and just look better quality.
Have a great day,
Dale