help ID'ing wires on encoder for mouse hack pls

[vintagegamer]

Please see the 2 attached pic of the existing encoder PCB from my Sega Monaco GP cockpit.

On the pic showing the back, the order of the wires goes: 1. white (far left), orange (2nd wire), blue (3rd wire), and yellow/red (4th wire).

After reviewing the board, I believe that wire 1 (white) is common/ground, wire 2 (orange) is one of the sensor wires (goes to IC1 on the front of the board), wire 3 is the other sensor wire (goes to IC1 on the front of the board also), and wire 4 is the +5.

My questions are as follows:

1.Can anyone confirm or deny my current thoughts on the 4 wires?
2. if my guesses are correct, where on the mouse PCB do I wire the +5 and the ground/common wires to?

I checked the original manual for this game but the schematics are crap unless you have your PHD in Electrical Engineering and Metaphysics. 

Thanks for any help!

VG

[vintagegamer]

Found the below site so I'm going to use it as a guide and hopefully give this wire-up a test tonight.  Stay tuned.

http://www.jstookey.com/arcade/720/720-arcadejoy.php

[boardjunkie]

From the front view of the board you have, those 74xxxx chips all have the same pwr pins. Looking at them with the little notch cutout facing up, the top R corner will be +5v and the lower L corner is gnd.

Clean those optos while you have it out....they don't like to work well with a good layer of dirt...

[dramaone]

can you confirm the id of wires on this opto board?
thanks in advance

[ed12]

the plus rail runs on the top of the pcb
the - or ground rail runs along the bottom (solder side)
it is clear as a bell in your first picture (top side) u can see where pin 14 goes for the ic's
on the bottm u can see the big trace going around 3/4's of the board = ground

ed

[dramaone]

Thanks, I dragged an older thread plus my understanding electronics are piss poor.

[dramaone]

the plus rail runs on the top of the pcb
the - or ground rail runs along the bottom (solder side)
it is clear as a bell in your first picture (top side) u can see where pin 14 goes for the ic's
on the bottm u can see the big trace going around 3/4's of the board = ground

ed

Sorry, I'm sure your explanation is clear but I still don't get it.

Please help a dunce.

Is wire 1 ( white wire ) plus or negative?

Thanks again

[dramaone]

Sorry, I'm sure your explanation is clear but I still don't get it.

Please help a dunce.

Is wire 1 ( white wire ) plus or negative?

Thanks again