Redknapp, 64, is the overwhelming favourite to replace Capello following the Italian’s shock resignation on Wednesday in protest at the decision to strip Chelsea’s John Terry of the England captaincy.
“There is no doubt Harry Redknapp is the best man,” Ferguson said Wednesday.
“The press have decided. Harry is the best man,” added the Scot, whose reigning Premier League champions are currently second in the table, just five points clear of third-placed Spurs.
“He has the experience and personality and the knowledge of the game. He has changed the fortunes of every club he has been at,” Ferguson said of his veteran English counterpart.
“He is the right choice.
“You should try to get the best man with the best qualities. A young manager has no chance.”
Tottenham are bidding for their first English title in more than 50 years and there have been suggestions that Redknapp, with the European Championships in Poland and Ukraine just four months away, could be a part-time England manager while remaining in charge of Spurs.
But Ferguson, thrust into a similar caretaker role with Scotland at the 1986 World Cup while Aberdeen manager following the death of Jock Stein, warned against a dual-role.
“I tried it myself with Scotland in Mexico. I found it very difficult.”