There are many ways to do something like this. As luck had it, this size cutting board left the corners protruding out which is perfect since that is where I will bolt my two separate ground leads. It also would be a good idea to bolt the positive lead at this time while it's accessible. Using the nylon bolts through the vent holes to maintain proper alignment I'm test fitting the vinyl tubing that will insulate my 8-32 bolts from the cell plates. Note that I've cut the vinyl tube to be long enough to go though both cutting block end pieces. This way it will keep the assembly bolts from coming in contact with the plates so they will maintain two separate cells.

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