Paul Taylor, of Valentine Close, Fareham, Hampshire, was also found guilty of three rapes, an attempted rape and a serious sexual offence.
Today, at Chelmsford Crown Court, Judge Mr Justice Owen said: "I think it is clear there was a sexual element to the murder of Sally McGrath.
"The evidence revealed a pattern of behaviour in which you lured your victims in under the pretence of giving them a lift home.
"You then drove them to a rural or isolated area and forced yourself upon them.
"Your predatory sexual attacks took place over 30 years ago but your victims have been left scarred for life.
"I have no doubt the brutal murder of Sally McGrath followed the same pattern and resulted from her resistance to your sexual demands."
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Norwich City manager Alex Neil has slammed his side for their "lack of hunger" after they were beaten by Brentford at Carrow Road.
After a bright cold start to the day cloud will thicken from the west and it will become quite breezy, though for most a dry day.
It's been the coldest week in the Anglia region since January 2013 with temperatures dipping close to -8°C.