Coupe GT A/C help, please

[Steinbru@VNET.IBM.COM]

My son took the '87CGT in to Jiffy for an AC pressure/leak test today.
Well, the Monk.., er, the mechanic was stymied.  There is only a high
pressure valve.  In Bentley, both high and low pressure lines have a
valve, and they are shown right near the compressor.  My son had the
book there, but there is only one valve.

Do any of you know what's going on here?

Were later models different?  I know the '86 5k only has a high pressure
valve, and Bentley specifies only check, evacuate, or fill at that point.
There is no "topping off" allowed.  My build date is 7/87.

--Gary  ('86's:5ks&5ktq+'87CGT  --PP here we come!)