Well. IMO it was hard to push her into that narrow space. And then it would be hard to get her out, and if, according to what he says, the girls were still on the seats, what did he do, push them aside as he dragged poor SW out the of narrow space? He would have, at the least, bumped against their little legs, or pushed them against the seat as he took her out.
Besides, it doesn't make any difference re sympathy or empathy (!!) towards him if he took her out first, or last after murdering the kids.
I don't believe it, and I don't know why he said that.
He left SW's body on a dirt pile while he murdered the children, one by one carrying them up the ladders and stuffing them in the 8" holes?
He was parked across the parking lot, by the well head, about as far as possible from the tanks as he could be.