I have since removed the stacker from the boot again and dissaembled it. I managed to manipulate the mech assy to slide the jammed CD back into the cartridge and was then able to remove the cartridge per normal. Incidently the motors and the sensors in this stacker are not available for purchase over the counter, even by someone else in the trade and apparently even Ford themselves find it hard to get parts for these stackers. Anyway I cleaned the rollers completely and cleaned the laser optics too. I also resoldered a bunch of dry joints on the P.C.B. that looked pretty bad and then made sure the mech assy was aligned properly before I reassembled it. I connected it back up in the boot and the stacker has been working normally since reinstallation. Fingers crossed that it lasts for a while longer...