I would check the control arm mounts real close. The ball joints of course but maybe a lose or worn out mount where they attach to the frame area. The turn left and over a bump noise contributes to my concerns. Maybe even look to be sure there is no problem at the rack mounts.
Sorry, updated thread while I was typing this in. Congrats on the fix.
By the way I also agree that when checking motor mounts for problems, I have a friend hold ******* the brakes and "goose" the throttle pretty hard to see how much the engine will lift on each side.