beatles first press

how do i determine a first press sgt peppers on capitol rainbow......both say smas 2653 on the album label but are positioned in deifferent locations on the label.....one says capitol 2653 on the spine and is significantly heavier in both vinyl weight and cover wiight...and has a 2653 printed over georges shoulder in the gatefold.....the other says smas 2653 on the spine?......is there any where i can look to find out what gives?......oh.......both are canadian presses and one says litho in canada...the other doesnt