Agree, looks like someone added a monte carlo bar. The additional braces for convertibles started around November '64, so your car is too early to have had them. The braces also included an under-dash brace to help with cowl shake. For driving, you might consider installing an export brace and remove it if you want your car judged for authenticity. An export brace really helps stiffen up any of the 1st generation convertibles.