A post circulating Facebook and elsewhere reads:
Nelson Mandela will die soon. Today, tomorrow, this week, next week. It won't be long. Remember this, he out-lived Thatcher. When he does die, and David Cameron jumps on the Mandela bandwagon, remember that in 1985 he was a top member of the Federation of Conservative Students, which produced the "Hang Mandela" posters. In 1989, Cameron worked in the Tory Policy Unit at Central Office and went on an anti-sanctions fact-finding mission to South Africa with a pro-apartheid lobby firm sponsored by PW Botha. Remember this when he tells the world he was inspired by Madiba.
The text I pasted is subtly different from the photo captured here - both are in circulation, but the former is privately shared, and I imagine susceptible to link rot.
The 1989 trip to South Africa, and its sponsorship by an anti-sanctions lobby firm is well documented.
I have found plenty of corroboration for the existence of the poster in question, produced by the Foundation of Conservative Students, but not the exact year it was produced, nor evidence that Cameron was a member of the organisation, and it so, when.
So, was David Cameron a "top member" of the FCS at the time these posters were produced? Is there evidence that he was instrumental in, or sympathetic to, the production of these posters?