2001 Other Jaguar Models Low Pressure AC

I recenly purchased an AC recharge kit (which I have purchased and used on my Expedition and my Jetta in the past) but I can't seem to locat the low pressure input on my Jaguar S-type. The fitting on the top of the unit is larger than the standard quick-snap fitting on my other two cars, so I was guessing that that was the high pressure (which I know not to use to fill). I searched the system and could not locate where to fill the system.

I asked the salesman at CarQuest and he called their AC expert and he said that the larger fitting is probably the high pressure and did not know where the low pressure would be on this car. Can you assist me here?

Thank you,