Theres a few things about converting a driving cab,
first you really need to make it compatible with both,
360 and 270 wheels.
I just had 270 and its a bit anoying only playing half the games.
Its not that hard to get the original arcade wheels to work,
to get a 360 to work u just need a simple mouse hack,
the good thing about the 360 wheel is its easy to change the sensitivity and speed of a mouse.
the 270 is fairly simple also ,just make/hack 2 button joystick lead the same as the diagram on the web sites.
the only thing about the using a joystick hack as a steering wheel is u are just using a standard joystick driver.
what i found was that in the some mame games like chase hq , when you went into the dip switch setting in the options you could select digital or analog steering .
where as in outrun you couldnt.
chase hq worked fine where as outrun wasnt so good.
(im sure it would work fine if more time was taken)
for the 270 wheel it might be easyer to use the insides of a pc wheel so you get a beter software driver.
I never spent that much time on it though as i havent got a spare pc for a dedicated mame driving cab.