There should have been a clear tube with a cap on one end provided. The ram is actually hollow with a fitting on the bottom, no mods should be needed to your bench. I replaced the tube with one a little longer, then drilled about a 5/8" hole in the lid from a tall clear Gallon water bottle. Make sure you leave enough length on the tube so that is slides up and down, within the container lid, to allow ram full extesion (up and down) without pulling out of the bottle.