Several Gers first-team regulars are struggling to be available for the meeting with Raith Rovers at Easter Road on Sunday afternoon.
Ian Black, Jon Daly, Nicky Law, Andy Little and David Templeton are all doubtful for the match through in Edinburgh due to injuries.
All five men have been working hard in training at Murray Park this week in a bid to be in Ally McCoist's starting line-up come kick-off.
And central midfielder Law, who strained his back in the 2-1 win over Brechin City at Glebe Park on Saturday, is optimistic he will make it.
But captain and centre-half McCulloch is confident the Ibrox club have the strength in depth they need to deal with the situation.
And he believes that, no matter who takes to the field in the capital, Rangers can complete the second leg of an unprecedented domestic Treble.
He said: "Obviously, if any of the boys who are out injured at the moment fail to make it they will be big losses for us.
"Temps, for example, will be a huge loss. He has had some injuries to contend with this season, but when he has played for us he has done really well.
"He has won games for us on his own at times. In the second half of the season he has been absolutely sensational. He is definitely going to be missed.
"As, for that matter, are the other players who are stuggling with injuries at the moment. Hopefully, they will all be available for the cup final.
"But we have got a big squad at Rangers. And that is for situations like the one we are in at the moment. We have got enough quality players who can come in and fill in."
Rangers were missing Black, Law, Little, Bilel Mohsni - who was suspended - and Templeton in the SPFL League One match with Arbroath at Gayfield last weekend.
And McCoist gave run-outs to Robbie Crawford, Sebastien Faure, Kyle Hutton and Arnold Peralta in a game that his side won 2-1 thanks to a late Aird from Fraser Aird.
In addition, youngster Calum Gallagher, who has impressed in recent weeks, came off the bench and set up Aird for his goal.
McCulloch believes that hard-fought match through in Angus will be invaluable to those players if they are involved against Raith in four days' time.
He said: "The game against Arbroath last weekend gave the likes of Robbie, Kyle and Arnold some game time. They all enjoyed good performances.
"It gave them the chance to play in a competitive match and if they have to come in against Raith I think they will be all the better for it."
McCulloch was inducted into the Rangers Hall of Fame at a star-studded dinner in the Hilton Hotel in Glasgow on Sunday night.
The 35-year-old was a worthy recipient of the honour due to his immense contrbution to his boyhood heroes' cause in the last seven years.
He has won every major honour in the Scottish game since moving to Glasgow - the League Championship, the League Cup and the Scottish Cup.
In addition, the former Motherwell and Scotland star was integral in Rangers reaching the Uefa Cup final in Manchester back in 2008.
And he has been a tower of strength, both on and off the pitch, since the Ibrox club dropped down to the bottom division at the start of last season.
McCulloch has, then, been involved in far bigger games in front of far bigger crowds than the Ramsdens Cup final.
Yet, he appreciates how important victory will be for Rangers in "The Journey" back to the forefront of the game in this country.
The last cup final that Rangers won was three long years ago when they beat Celtic 2-0 after extra-time in the League Cup final.
McCulloch said: "This is a cup final. It is the chance to win a trophy and we have to take it seriously.
"For me personally, it is a chance to lift another trophy as Rangers captain and that is not something that I would ever take lightly.
"We will all be up for the game and are all looking forward to it. We are definitely not taking it for granted that we will win it.
"Raith Rovers are a decent team with decent players.
"Nor will we be using it as a warm-up for our Scottish Cup game against Dundee United at Ibrox next week. This is a cup final. It is not preparation for a game.
"We need to deal with this game first and then we can worry about the United game. I am sure that we will all be fully focused on the game in hand."
Rangers have stormed to the third tier title this season due in part to being a full-time team in what is a part-time division.
But McCulloch is confident they will be able to overcome professional outfit Raith, who knocked Hibs out of the William hHill Scottish Cup at Easter Road earlier this season, when the two sides meet on Sunday.
He said: "There is not that much of a gap between League One and the Championship in my opinion.
"We have only really played Falkirk and Queen of the South from that division in the 2014/15 campaign.
"But we have beaten them both. And both of those games were away from home. That tells you that there is not much in it.
"Yes, it will be a step up in standard from what we are used to this weekend as Raith are a full-time time.
"But we will be ready and we are good enough to win - no matter who is in our side when the match gets underway."