Capital letter indicating new driver is attached to rear of cab first (6)
I believe the answer is:
lisbon
'capital' is the definition.
(capital of Portugal)
'new driver is attached to rear of cab first' is the wordplay.
'new driver' becomes 'l' (learner drivers have L-plates on their cars).
'attached' becomes 'on' (I've seen this in other clues).
'to rear of' suggests the final letters.
'first' is a charade indicator (letters next to each other).
The last letter of 'cab' is 'b'.
'on' put after 'b' is 'bon'.
'l'+'is'+'bon'='LISBON'
'letter indicating' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for lisbon that I've seen before include "Slob in Portuguese city" , "Capital of Portugal" , "Portugal's capital" , "Capital city and Treaty" , "European capital" .)