New chief executive Green appears to have won over a sceptical Light Blue fanbase since taking control at Ibrox after the disastrous Craig Whyte era.
But McCoist admitted last night that he has still to win the chief executive's overall backing – despite the strides that are being made to revamp the fallen Glasgow giants.
McCoist said: "We have to trust each other. By that, I don't mean 'no, I don't trust him'.
"I don't think for a minute he will trust me 100% at this moment in time. Trust has to be earned. It is the same as respect. You don't give someone trust, you don't give someone respect. You earn it. That is where we all are at the moment. I would have to say, I am very, very much encouraged by where we are at the moment.
"We have miles to go. We are in a far better place."
Despite a rocky opening few weeks at the Ibrox helm, Green has earned the backing of the Ibrox legions as he prepares to float the club on the Stock Exchange.
The Yorkshireman's bullish style and no nonsense approach has won him many supporters and while McCoist admits the pair do have their disagreements, he insists the pair are on the right track to forging a successful working bond.
He said: "In my opinion, the most important relationship at any football club is manager and chief executive, it has to be.
"It is safe to say that him and I won't agree on everything, there is no doubt we won't agree on everything.
"He is probably as forthright and demanding and in your face as anybody.
"But, I have to tell you, I don't mind that.
"I spent the majority of my time here fighting with team-mates, but we all wanted to get to the same end.
"I am not saying that we fight all the time, far from it. It is still the early stages of the club's transformation.
"I think we have a very healthy working relationship.
"He phones me up, we have a cup of tea and we talk. He is really forthright.
"He knows what he wants for the club. If that means me getting one or two players less in the transfer window than I wanted then that's the case."
Meanwhile, Rangers fans will have to wait a while longer to witness David Templeton's return to action.
The winger is back in training after being sidelined since September 15 with ankle ligament damage but will not feature this weekend.
McCoist said: "The good news is the wee man is looking healthy again.
"He's out on the training ground and I would hope he would be back playing for us in the not-too-distant future.
"This weekend has come a little bit too early for him."
On the chances of Templeton making his comeback against Inverness in the Scottish Communities League Cup on Wednesday, the manager added: "Big game, big call. We'll see how he is on Monday. I wouldn't rule anything out.
"The most important thing, when he does come back, is that he's 100% fit and ready to go again."