i'll give you some tips/advice
do not let ANY and i mean ANY dirt get into the system. use a non hydroscopic oil like that of duracool. install a new receiver drier. install viton o-rings on all lines if you can. o-ring kits can be had from e-bay for fairly cheap.
do you think your missing lines? don't know which ones go where? the smaller diameter hose is the high pressure line going from a/c comp to condensor, then to evaporator. low pressure (big hose) goes from evap to comp and most have this round cylindrical chamber somewhere in between. i forget what its for...