I replaced the 2 belt system, on my 1971 Duster, with a 3 point seat-belt.
Back in the early 70s, I chose to only wear my lap belt and not the shoulder belt. To make a long story,short: 13 broken ribs and one fractured vertebrate.
I have never been in a vehicle without a 3 point seat-belt system since. And wear it religiously
Question- I too, have a ‘71 Duster, new headliner already in place, so I can’t see . Do ALL 71’s have an anchor for a 3 point lap & shoulder belt kit? I am operated C 1-7 , and I’m not endangering myself either with just a lap belt.