Quote Originally Posted by 68Charger View Post
1980's would be T-lock... makes repairs nearly impossible.

my house used to have a T-lock roof.. little wind damage at one end and it was done... replace it all (not made at all since 2003)
So many T-locks have been replaced over the years under the premise of "oh they don't make that shingle anymore and we can't match it" that there are warehouses full of T-lock shingles. You can repair T-lock by just removing a shingle to use as a template and cutting new shingles out of 90lb roll roofing. Maybe not ideal, but certainly serviceable.