I concur with my esteemed 427 based colleagues.
The AC Ace foot boxes I have seen --all have been metal.
Photos below;
1. 1957 AC ACE footbox.
2. CSX2001 Engine Bay
3. CSX2001 Passenger footbox
4. CSX2001 Driver Footbox
5. 1963 AC ACE -- the LAST AC ACE ever imported to the USA.
6. 1963 AC ACE Footbox - Drivers Side
7. 1959 AC ACE Drivers Footbox
