Last to finish university? Engineers! (6)
I believe the answer is:
endure
'last' is the definition.
('endure' can be a synonym of 'last')
'finish university? engineers' is the wordplay.
'finish' becomes 'end' ('end' can be a synonym of 'finish'**).
'university?' becomes 'u'.
'engineers' becomes 're' (Royal Engineers).
'end'+'u'+'re'='ENDURE'
'to' is the link.
(Other definitions for endure that I've seen before include "Bear, stick it out" , "Put up with - last" , "Bear, suffer" , "'Last, bear (6)'" , "Suffer, tolerate" .)