Wirey Problem(with pix)

[wxman1]

OK, I'm wiring a custom dash for my 69 C10 P/U.
(See first pix) I'm going to use an electrical oil pressure guage
instead of the old copper line/analog guage. Well I installed
and electrical oil pressure sender in the oil port. I've installed a new
engine wiring harness with the Dark Blue wire connected to the
spade lug on the oil pressure sender. So now I'm trying to wire
in the guage. The dash connector pinout in the wiring diagram
(See second pix) is Fig 53 from the 1969 Chevy Truck Service manual.
The actual dash panel wiring connector (See third pix) doesn't match
the wiring diagram. The connector has (one one side) a black, 2 grays,
dark blue, light blue, light green and a black wire. That doesnt match the
wiring diagram. At any rate, I've got everything wired up except the
oil pressure sender. The oil pressure sender is connected to a dark blue wire
(as per the engine wiring diagram) which goes through the fire wall.
The problem is I can't find this darkblue wire in the dash harness.
There is a dark blue and light blue wire in the harness and those are the
right and left blinkers.

Can anybody help on this problem?

Jim
Mt Juliet