Thanks for that link. Ill check those out as an option.
Still trying to figure out a way to use stock seatbelt. May even try to move the guide with spacers/washers. Or see if the Carbon Miata extenders would work in the bolt location behind the roll bar that mounts the bar to the car.
Car isn't exactly my daily driver. I drive it once or twice a week to work and back, if that. And when I am able to run a few errands if my son is at my parents'. And its only on the road 6 months out of the year.
What is the concern with 4 point harness? I used them in my previous Miata. And that car was my daily driver.