I would use the continuity test / diode check on a multimeter. Put one test lead on the +5V input on CN1, then use the other test lead to check the pins on 40-pin connector. You will hear a beep when you have found the +5V outputs. Do the same with ground.
Correct.
Thanks for that, that's also help me learn about the pinout set on the control lever
Today, I took sometime to assemble a button setup which build with some materials from my arduino kit ( you may laungh on this

)
But apparently that's didn't work, I think that maybe a cable issue.
For now, I think I will wait to get the projector and see what's going on first.
I somehow tried to bid the projector from Y!auction JP and waiting for the shipment now,
and I can foresee that may take few months for importing it to europe if I go for the cheapest plan
If the game can process further and booting into the actual game, I will then starting to buy crimping tools, cable, connector head, so on for making a proper control.
Damn, I really want to see the game running again.
I hope I can still have your help at that time, much appreciate your help so far, that really make a dumb like me learn a lot
btw. In mean time, I now look at the openjvs and IONA, so If I eventually can't get the control lever work, hope these things can be an alternative solution.
Back in the day,I should wait for someone sell a full set of control (necessary cable and pedall) rather then just buy a set of lever, just too dumb I am...