Americans behind bars try bottles right on top of shelf after measure of ale (9)

'americans behind bars try bottles right' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'top of shelf after measure of ale' is the wordplay.
'top of' suggests taking the first letters.
'after' says to put letters next to each other.
'measure' becomes 'yard' (yard is a kind of measure).
'of ale' becomes 'bird' (I can't explain this - if you can you should give a lot more credence to this answer).
The initial letter of 'shelf' is 's'.
'yard'+'bird'='yardbird'
's' after 'yardbird' is 'YARDBIRDS'.

'on' acts as a link.

Can you help me to learn more?