I am interested in purchasing a Wayne 276 that appears to be in good condition on the outside, but the seller cannot get the sliding skin lowered. Seller tried to bear hug it and pull down, but it would not budge. I guess it could be locked or the pulleys rusted. I am hesitant to purchase it without knowing if the clockface and other guts are still present. Will the pump have to be disassembled to lower the sliding skin? Any tips on what to try?