Toyota Repair: 91 Toyota Pickup A/C, service valves, c lines

Question
Hi, I am trying to find the low pressure side inlet valve to put a guage on an perhaps charge & lube but I cant find it. I found the high side (red cap and on the compressor) and found the receiver & sight glass. Where did I go wrong? Thanks, Dave.  

Answer
Look near the firewall on the right side where the A/C lines enter into the passenger compartment, the low pressure service port is within about three inches of the firewall, as a matter of fact, both the high and low service valves are located there.