I need to know exactly how the rack is connected,I have the 2 front screws removed on both the front and rear mounts but the 2 longer ones on both the front and rear mounts wont come out.Stripped maybe?I pull up on the rack while unscrewing but cant get them to catch and come out.Is the rack "plugged" into the roof with rubber grommets maybe? pleas don't tell me I have to remove the headliner to acces a couple nuts under the roof. Thnx,Vince