I recall the shroud was metal in 1965 and those are very rare and valuable today. Most probably rusted away or were just tossed by a gomer mechanic decades ago.
1966 Also, they made a 19” & a 22” one, metal may have been available in 64 a-body also not sure. They were 2 piece shrouds, easily lost if removed and yes many rusted away....definitely rare
