So you have your gun striped and lubed and your piston washer on the piston. Replace the piston in the cylinder (often with leather washers you have to push on the edge of the washer to ease it past pivot holes or where the cocking slot ends) and then the mainspring and guide. Replace the thing the rear stock bolt screws into with the boss facing the rear of the cylinder. Use your bit of wood to compress the spring enough to get the bolt that secures it back in and tighten it up. Replace the spacer washer in the cylinder and then the trigger unit and locate it with its pin. Replace the barrel in the breech jaws and tap the pivot pin back in then relace the cocking arm if you removed it at the start. Replace action in stock and put foresight back on. On the one I did, I swapped the socket headed front stock screws for slot heads. They are 2ba thread and about 10p each from an engineers supplier. The rear stock bolt is 0Ba but you may have to file up the head to fit the trigger guard. Like I said earlier on, try a G25 spring to give it an easier life. If your stock broke at the front (assuming that the gun would have to be a plinker now) get two lugs welded at the front of the cylinder and tap them 2Ba and drill the stock lower down to fit them in a better position.