I bought a set of 3 points, one for me and one for the passenger for about $275. It wasnt cheap but it was worth it, if you get in a wreck in the front or back the truck will be unscathed but you will eat steering wheel and your passenger will eat steel dashboard, even with 2 points.
Buy some 3 points, feel safer and be safer. I'm sure you can go to a junk yard and if you are a good enough do-it-yourselfer buy cheap 3 points from a wrecked car (proven to work haha!).
My middle passenger has a 2 point from an old Caddy, not a 3 point but better than nothing. It's alright for the middle to have 2 point rather than the right passenger, you can always put your arm across his/her chest depending on how strong you are and it will save them a head injury.
As for your statement "life is a little chancey anyways, right?", that's all fine and dandy if you are the only one affected, and it's also partially my view on life. But when it comes to other passengers, I feel responsible for them and let's face it, drum brakes ain't exactly Brembo's.
If you want to go with 2 points, as I said earlier, better than nothing. I would take my '65 without any belts rather than a Honda Civic or Toyota Camry, I don't care how good the safety rating is, cause the tests don't factor in a new Chevrolet 2500 HD Duramax turbo diesel with a 6 inch left collision, which would involve a tire in place of the head of the car driver.
Just somethin to think about.
-Preston
that's the perks of driving pre 65. i did install a lap belt for my wife on the pass side. i just used some out of another truck.