Being a 90 it has the 5 degree cut gears, does it have a "RED" cable going to the drive? There is also an upgraded ignition pack! The Cobra is actually a stronger drive than the Alpha but decent mechanics are getting scarce, all clutch dog shifter drives have similar adjustments. The OMC has one more thing that should be checked, that is the shift cavity in the gimbal. Many times water gets into the making shifting a pain, cable pull is critical it is measure in Oz"'s with a fish scale to make sure the cable drag is within spec.
Phil
No matter what your beliefs are "GOD BLESS AMERICA"
Fully retired marine tech near 60 years in the biz.