A news photographer from KDKA captured the first steps of the makeover on Monday -- showing the massive Heinz ketchup bottle sign being removed by a crane and placed on the ground.
Some of the construction workers on site even used it as a photo opp -- posing in front of the bottle after it came down.
While some fans are hurt over the change, Steelers President Art Rooney II is excited about the new name ... saying in a statementthe org. is "excited to partner with Acrisure for the naming rights to our stadium."
"We are very appreciative to partner with Greg Williams and his company, and we look forward to a long, beneficial relationship for years to come."
Steelers Hall of Fame coach Bill Cowher likes the name change as well ... adding, "Pittsburgh will always be a very tough place to play."