Got on well with but had a collision with one classy guy (3,2,3)
I believe the answer is:
hit it off
'got on well with but' is the definition.
I know nothing about this answer so I can't tell whether this works.
'a collision with one classy guy' is the wordplay.
'a collision' becomes 'hit' ('hit' can be a synonym of 'collision').
'with' means one lot of letters go next to another.
'one' becomes 'i' (Roman numeral).
'classy guy' becomes 'toff' (I can't explain this - if you can you should believe this answer much more).
'hit'+'i'+'toff'='HIT IT OFF'
'had' is the link.
Can you help me to learn more?
(Other definitions for hit it off that I've seen before include "Click with someone" , "Agree - get on well together" , "Become compatible and friendly" , "Get on well - with a blow?" , "Be well suited" .)