A 0-0 draw at Montrose on Saturday lunchtime appeared likely to delay Rangers' title celebrations, but Queen's Park's 1-0 defeat by Elgin later in the day confirmed McCoist's side as champions.
Rangers had been demoted from the SPL last summer after being liquidated and being forced to reform, and McCoist acknowledged it has been an eventful season for the club.
"We're delighted," McCoist told Sky Sports News. "People have been asking us for many weeks where we would like to win it, but we've always been of the opinion that it can be absolutely anywhere at the first available opportunity, and thankfully it was today.
"It's fantastic. There were a certain amount of people who would say they expected it from us, but that's never been the case from anybody within the club.
"We knew it would be very difficult, and that has certainly been the case. I'm thrilled for the players, the staff and the incredible supporters.
"The best way to describe it is that it's the first step on the road to recovery and back to where we want to be."
Discussions are currently ongoing regarding the future of Scottish football and Rangers will have to wait to see which division they will be playing in next season.
However, McCoist is adamant Gers deserve to be promoted and believes it would be unfair for any restructuring of the league to come into effect for next season.
He added: "What I would like to happen would be promotion for our club. Having won the title, I think the players and the fans 100 per cent deserve that.
"In my opinion, you don't move the goalposts during the season. Everyone starts the season knowing the rules. We've been fortunate enough to win our championship and I would expect progression to SFL2.
"I think moving the goalposts in the season is unfair on everybody. I'm all for change and I'm all for dialogue, and sitting down and getting the best possible outcome for the benefit of Scottish football, which is vitally important.
"But, in terms of the immediate future, natural progression is promotion for Rangers."