One of the biggest differences between the PS1 and the PS2 is the matter of the PS2 having all analog buttons. What this means [for you] is, you have to find a way to modify the wheel so it's left and right signals (wheel --> PS2) are recognized as if they are coming from the left analog stick of a Dual Shock controller. My best advice for this is to take apart a PS1 controller and fond the wire that goes from the analog stick to the PS2 plug in and then switch the wire accordingly on the wheel's plug.
I'll simplify it...
Say that you took apart the PS1 controller and found the wire from the analog stick...so you follow it to the plug-in part that connects to the PS2. This wire is in a certain slot on the plug. Soooo ... what you need to do is take the wire that is on the wheel (from the wheel itself) and put it into the slot that corresponds to the analog stick in the plug part.
Hope that helped.
And BTW, I take no responsibility if you mess up, if it this setup messes up your PS2.
Best of luck,
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