Michael,
If it's a small black L shaped plate appox 3/4 X 1/2, it screws into the inside of the boiler and fits into a slot in the chassis to hold it in the boiler. the addition of 2 screws in the front under the pistons secures the boiler. As for the smoke unit usually the addition of fluid and some time to soak will bring it back to life. In severe cases the old fluid congeals and blocks the smoke exit hole. The 2 connections on top of the smoke unit lead to nichrome wire which is wound around an angel hair core which acts as a wick. The wire heats during application of voltage and produces the smoke. Rewiring the unit is slightly complicated as you need the correct components and the correct amount of turns of wire to produce a balance of no smoke or a burned up unit. Kits are available through AF parts dealers and rewiring services are also available. Clean the armature with a pencil eraser and clean out the slots, replace the brushes if necessary. The brush springs have wings when installing, be carefull. The reverse unit is your biggest challange.
Rich
