You’re running out of time to drive the old Steilacoom-DuPont Road overpass of I-5. It’s scheduled to close for good Sunday morning, as the new interchange opens to all traffic. Nearly three years of construction on the new interchange should wrap up early Sunday morning when the new overpass and on- and off-ramps open to traffic. The old overpass just doesn’t meet the needs of the growing communities in DuPont and around Joint Base Lewis-McChor…