New trailer. Where to weld the D rings?

Winches on a car trailer sure are nice, aren't they? I used to travel a little with a good friend (RIP) that enjoyed just going and getting the occasional car to clean and flip. Man that winch made it easy.
Yeah, I did the come-along and a strap or chain pull too many times. And had to tilt the trailer and ride the car down on the way off. That only works if the car has brakes, lol.
Even the tiny 2500 lb was a MASSIVE improvement, even though it strained occasionally on a 3500/4000lb car. I think the nine ton I got now could put a car on the roof of a house.
It'll sure set one down gently off the trailer, even if the car has no brakes.