I have a 1988 GXL with factory air and I need to replace the receiver/drier and pressure regulating device which, according to all information I can obtain, is a TXV. There is no TXV unless it is in the passenger area with the evaporator coil. Even though the A/C system uses a receiver/drier in the high side it appears there may be a orifice tube in the two piece line between the receiver/drier and the evaporator coil inlet. Help! I am burning up and need to get proper parts before proceeding.