when trying to lower top, a motor sound comes from over w/shield the top does not move. when try to manually unsrew latch it just skips every 1/4 turn. it looks like cover for latch won't come off unless top is released. anyone have an idea how to unlatch the top or does cover have to be cut open? any help appreciated. george 386 846 6905 if you want to call me, i'm available most of the day. if i don't answer, lv msg. i'll call back