Sorry about the poor scan. Where is this gif file/picture you mentioned?
From what I can read from this schematic, in the manual, there are 2 vacuum ports, and 2 electrical connector inputs, each with 3 pins each. Only 1 pin out of the 6 is a ground. I don't know how you'd tell which one it is if the unit isn't in the car attached to the harness. It's marked '2' on this diagram, so if you have a 3 pin connector, the pin may be marked with this number.
The 'eggcrate' is a vacuum resevoir, I believe mounted under the package tray on a 126. The schematic doesn't show a line to one of these. You wouldn't need it anyway to operate the pump.
Perhaps someone who has worked on one of these can help with identifying your electrical connections....

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1986 560SL
2002 Toyota Camry
1993 Lexus