A method in the 4 Hour Body (yeh, I know) to correct anterior pelvic tilt was to lie flat on your back, put one leg bent on a chair, and the other leg straight with the foot resting on a low object such as a couple of thick books.
You now press your spine flat against the floor and hold this position for 25 minutes. Then you switch over legs and hold for another 25 minutes. The whole process takes nearly an hour, which is surprising, because usually that book is about taking various short-cuts. Over time you gradually reduce the height of the stack of books until your straight leg is resting on the floor.
But anyway, has anyone tried it, and would it work? All I know is I’ve done all the rkc planks, bird-dogs, glute bridges, fire-hydrants, rollovers to v-sits and hip flexor stretches in the world and none of it has helped my anterior pelvic tilt one bit.