The People says McAllister will watch Windass and Brown in a special closed-door game tomorrow.
Hull want to off-load players after an influx in the summer, and Leeds need experience to boost their League One promotion push.
Windass, 39, scorer of the play-off winner at Wembley, has only figured in one Premier League game and may fancy a last challenge.
His former club Bradford are also keen.
Centre-half Brown, 31, is settled in the area, so a move west along the M62 could suit him.