The first stainless steel plate and one PVC spacer ring are shown. There is a PVC spacer ring also between the PVC end plate and first SS plate. A 35mm piece of 8mm ID 12mm OD rubber hose is slid over the bolts to isolate the bolts from the plates and hold the plates in place. Note that it would have made more sense to drill the gas vent hole to the upper left corner of the plates, so that draining the all of the electrolyte out of the electrolyzer would have been easier.
A side view of the cell stack with several SS plates and PVC spacer rings in place is shown. Note the soft PVC sheet material in the background with the cut outline drawn with a permanent overhead transparent marker pen.