[Closed] anyone know about bleeding coil shocks (after service)

Got a Marzocchi Roco RC coil that I have had apart to replace the shaft, and on reassembling and bleeding I can't get all the air out.

I didn't have a proper bleeed syringe so just sanded down the nozzle on a plastic syringe and screwed it into the bleed hole. This seemed to give a good seal but I couldn't get all the air out of the shock, and bubbles kept coming out of the shock body into the syringe. Do I really need a proper threaded bleed syringe or should it work with just a push fit??

Also does anyone know how sensetive the floating piston depth inside the piggyback chamber is? Will different floating piston depths noticably affect the characteristics of the shock?