If it's anything like body lifts compared to suspension lifts, there is a difference. Suspension drops lower the whole truck, body drops would lower only the cab and bed.
Well, every body panel would be lowered, hood should still be at the same height. Have you seen any images of trucks with body lift? You can clearly see the chassis better than stock body mounts... I'm guessing here because after all, I've got a 4x4, so the whole body would be lowered if I'm correct, not the chassis.
or you can modify the frame and leave the floor relatively stock...... for more head room. or chop tops!!!!!!!!!!!!!!!!!!!!