lower unit issues

heres the story I bought a used 225 that was supposed to have a rebuilt lower unit. when I put it on the boat and put it in reverse the prop would spin even after cable adjustment. so I figured that the shift rod may be out of adjustment and decided to to check and change the water pump. well I adjusted the shift rod(it was crooked) set the height at 21 15/16. after fully adjusting the cable it still would not go into reverse so I thought I would try to a different setting on the shift rod so I moved it to about 22 1/8 which seemed to max out the shift rod because it got hard to turn. put lower back on and it seemed to go in reverse fine. finally got to go to the lake and when I put it in reverse ti does mot engage just make a clicking noise. any thoughts? any reason the shift rod would get hard to turn i figured it would just unscrew out?

Now my question i have the lower from my 2.6xp(235) still. from everything I can tell it will work on my 225 if I change the shift rod is that correct? is there any thing else that needs done to it?
thanks

may have to have the drive shaft changed too.

Strange situation here. The shift rod would be correct at the first setting, then, for fine tune adjusting, you could use the black trunnion nut where the cable enters into the engine compartment. If the adjustment of the cable does'nt help, check for any slop in the shifting mechanism where the connection is made at the shift rod. If all else fails, you may have to open the case and check the internals for the problem. Check the rear bearing carrier and see if it has moved rearward, this actually locates the horizontal distance for reverse gear. If the case has taken on water, it could freeze and push the R.B.C. out the back. E.P.

In addition, the 235 case will work, but the driveshaft is too short and would need to be changed to the later style. E.P.