Had hard time lining up pretapped hole on bottom cover. Need to incorporate alinner to keep filler from leaking from weighting material inside base. Magna-Matic response: A liner is not necessary if you per the instructions use 3/4 washed stone as a fill for the column. Do not use sand as it can hold moisture. Regarding the alignment of the bottom cover - most likely the column was too tightly compressed - if the column bolts are not fully torqued there will be enough room for the bottom cover to fit in and line up.