The Dunedin men will marry tomorrow, but their move has horrified gay groups.
The pair are heterosexual best mates.
Engineering student Mr McIntosh (23) and teacher Mr McCormick (24) will tie the knot to win a The Edge radio station competition and a trip to the 2015 Rugby World Cup in England.
Mr McCormick said from Auckland yesterday opposition to the wedding was understandable but the pair never intended to offend anyone.
''We are not here to insult anyone. We are here to do our own thing and travel our own path.''
Mr McIntosh said the wedding was not mocking the institution of marriage.
''It's just seeing how far two good mates would go to win a trip to the Rugby World Cup.''
''We picked up our wedding certificate and the nerves are starting to really hit home.''
They will marry in front of 60 family and friends at Eden Park, Auckland.
Mr McIntosh said most guests would travel from Dunedin and Central Otago, paying their own way.
A celebrant would make the union legally binding and Crowd Goes Wild television presenter James McOnie would be MC.
The pair said their wedding vows would touch on their friendship and recall their time playing rugby together at King's High School in Dunedin.
They were undecided if they would take hyphenated surnames and who would walk down the aisle.
The couple's wedding song is Cruisin', by Huey Lewis and Gwyneth Paltrow.
Mr McIntosh said he thought the marriage would last at least two years.
Mr McCormick, a teacher at Musselburgh School, said the friendship began after the two met at Pirates Rugby Club in Dunedin when he was aged 6.
His family, like Mr McIntosh's, was excited about the wedding.
''They're backing us 100%,'' Mr McCormick said.
However, gay rights groups have condemned the union.
Otago University Students' Association Queer Support co-ordinator Neill Ballantyne, of Dunedin, said the wedding was an ''insult'' because marriage equality was a ''hard fought'' battle for gay people.
''Something like this trivialises what we fought for.''
The competition promoted the marriage of two men as something negative, ''as something outrageous that you'd never consider'', Mr Ballantyne said.
LegaliseLove Aotearoa Wellington co-chairman Joseph Habgood said the competition attacked the legitimacy of same-sex marriages.
''The point of this competition is that men marrying each other is still something they think is worth having a laugh at ...
''Maybe on the day that statistics around mental health for LGBTI (Lesbian Gay Bisexual Transgender and Intersex) people are better, when high schools are safe places for LGBTI youth, we can look back on all this and laugh.
''But competitions like this don't bring that day any closer.''
