Let me know how you go with this - i have a very similar unit with one wheel out of alignment, Trying to work out exactly where its meant to sit is a nightmare..
the only way i could think of doing it was to wait till it paid out on jackpot - of course this was not read on the wheels, but seeing as jackpot is only 1 chance out of all of them then i could work out where to move the paper details to - yes??
Well after exhaustive playing over a few weeks, i finally hit Jackpot - walked away to get a cup of tea and then pull out the mech and move the details round... came back and my son had stuck some money in and was happily playing away asking me why i hadnt fixed it yet...
still havent hit jackpot again