273 Closed Chamber Heads

[Green Monster]

Did Closed Chamber Heads come on the Commando 273ci ?
Thanks

 

[Cuda Al]

As I understand it, all 273 had closed chamber heads through 67, in 68/69 they had open.
The 2bbl and 4-bbl used the same heads (in a given year).

Alan

 

[Green Monster]

Checked numbers 66 - 67 we're closed chamber.