A full install starts with pulling the old door and checking what's underneath it - track, jambs, header, and the spring setup. On a house from the early 80s we usually find standard torsion springs mounted on a single shaft above the opening, which is the setup most new doors are built to use, so the hardware swap is usually straightforward. We square the new track to the opening, hang the door section by section, set spring tension to match the door's actual weight (insulated doors are heavier than the single-layer steel ones they usually replace), and balance the opener to the new door rather than leaving old settings in place. The whole job is done in one visit once the door's on site - the measuring and ordering is the part that takes lead time.