Trunk warmer, result of sun on back of Buick Super (4,3)
I believe the answer is:
tank top
'trunk warmer' is the definition.
The definition suggests a singular noun which matches the answer.
'sun on back of buick super' is the wordplay.
'sun' becomes 'tan' (both can mean to get a sun tan).
'on' is a charade indicator (letters next to each other) (in a down clue, letters appear on others).
'back of' suggests the final letters.
'super' becomes 'top' (I can't explain this - if you can you should give a lot more credence to this answer).
The last letter of 'buick' is 'k'.
'tan'+'k'+'top'='TANK TOP'
'result of' acts as a link.
Can you help me to learn more?
(Other definitions for tank top that I've seen before include "Sleeveless pullover" , "Item of gear" , "piece of clothing" , "knitwear?" , "Young woman might appear in this" .)