Originally Posted by TimJ
So you're able to index over 5 gears? You should still measure the freewheel, since it indexes with it the spacing will be close to what it's supposed to be.
The freewheel is a very common Shimano unit (MF-TZ30 or something like that) with a 5.3mm spacing. So the derailer intended for Ultra sprockets should undershift by about 1.5 mm in 5th gear, and derailer for Accushift sprockets should overshift by about 1 mm, if Sheldon Brown's data is correct. I'm going to try measuring it tomorrow.