LMAO!
First off, the 1956 Catalog image of the Corvette is a repeat of the 1955 model image. It depicts the 1955 only seat and the long tong 55 only Mayweg rack. Can't tell if that 56 image shows the much needed 1955 cable clip on the chain guard though. The seat in post #2 is the correct seat for a 56-57 model. Best of luck finding a decent one of those, they weren't all that durable. The 58 models were the first to use the better Mesinger and that's what I would use to replace a 56-57 seat if an original can't be found.
1958 Mesinger
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