I would say 5+6 would be better but it won't affect United.
No. of british players for United = 14: Wayne Rooney, Owen Hargreaves, Paul Scholes, Danny Welbeck, Ben Foster, Rio Ferdinand, Wes Brown, Darren Fletcher, Ryan Giggs, John O'shea, Gary Neville, Darren Gibson, Johnny Evans, Michael Crarrick. MUFC has more british players than Chelsea & Liverpool put together.
Manchester United 2008-09 Season - Trophies & Records