120 lower unit question

[HAV2FISH]

I am replacing a broken shift cable so while waiting for it to arrive i decided to drop the lower unit and replace the impeller. When the cable broke the motor was in forward so when i removed it i put the motor in neutral before removing the lower unit. Now that the lower unit is back installed with out shift cable installed yet, I can manually put the motor in forward and reverse however its stiffer it get it into reverse. In neutral the prop will spin freely in both directions in forward it will only spin in one direction but in reverse it wont spin at all. Im thinking when i put the lower unit back on the motor i didn't' line up the splines properly. I don't want to install the new shift cable start the motor and damage anything.