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Doing some clean up on my frame (68 SWB Chevy ) Someone previous to me put a trailer hitch on the truck with some booger welds. Removed hitch and found cracks in frame i believe they were trying to hide. Nothing I won't be able to fix. Above cracks in the frame, inside the c-channel of frame there are some pieces of angle iron bolted in place. They are the only pieces on the frame not riveted in place. I don't think they are factory. Can anyone confirm or deny this for me ? Thanks [ATTACH]Attachment 1516335[/ATTACH]