How do you go about putting a freezeplug on the back of the motor on a 1988 town car?

Do you actually mean the back(rear)of the motor or the rear side? Dont maen to pry but are you SURE its a freeze plug? These motors had a real problem with the rear(usually the pass side) intake leaking coolant. Anyway if you mean the actual rear of the block you have to remove the trans. If its a freeze plug on the head depending on the room behind the head to the firewall,I think I would pull the head. Freeze plugs pry out(something like a screwdriver through the middle and pry) and are driven in. Parts place do have freeze plugs with a nut that you can toghten instead of driving a plug in.Ive never used one may be easier.