Swapping a garage door panel by panel is not a weekend project, and on a door this age it's riskier than it looks. A torsion spring holding up a 1989-era steel door is under real tension, and the tools to wind it safely aren't something most homeowners keep in the garage. We'd rather tell you that upfront than have you find out the hard way.
Where a homeowner can reasonably do their own work: swapping weatherstripping, lubricating rollers and hinges, or replacing a cracked window insert in an older panel. None of that touches the spring system.
The other thing worth knowing before you start: if the opening itself has shifted over thirty years, a new door hung on an unsquared jamb will bind no matter how good the door is. That's a carpentry problem before it's a garage door problem, and it's worth having someone check plumb and level before any door - new or used - goes back in.