Former captain Danny Orr will remain in temporary charge for Friday's Tetley's Challenge Cup fourth-round tie against Leeds at Headingley as the Tigers ponder their choice as Ian Millward's successor.
The club are also considering an offer from former coach Stuart Raper to return from Australia to assist Orr until a permanent appointment is made. "We're well into it," Gill told Super League TV. "We've had quite a few applications and we've pulled a few names out."
He added: "At the moment we're quite happy with Danny and Richard Tunningley who are holding the reins and we've also had an offer from Stuart Raper which I'm considering. I've got to get it right. I don't believe it's something I need to rush into."
Veteran coach John Kear, who was born in Castleford, has been linked with the post and, although Gill says no contact has been made with Kear's current club Batley, he admits he would like to appoint a British coach.
"My preference - and it's not necessarily the preference of the board of directors - is for a British coach," he said. "I want someone who can put some structure back into the club and have some input into the development of players."
Meanwhile, as England international Rangi Chase edges ever closer to a move away from Castleford, Gill has revealed the player was the subject of an illegal approach.
Gill confirmed that Chase has expressed an interest in returning to Australia, mostly likely to his old club St George Illawarra, and that the Tigers would not stand in his way if he was adamant about a move. But Gill insists that no request was made for permission to speak to the 2011 Man of Steel, who is contracted to the Super League outfit until the end of 2015.
"It came as a bit of a shock when I found out that had been done," he said. "But I can't help that, that's been done and it's time to move forward. I only want people who want to be at this club."
Chase has been named in Orr's squad for Friday's Cup-tie, which looks increasingly likely to be his final game for the club.