Yes, you will need to pull the plastic sheath through the shift bellows. The procedure would be the same as a gen 2 shift bellow. There’s some good you tube videos on how to do it.
If you know the measurements of the old cable are within spec and you are not replacing the cable, I start at the shift linkage on the engine. I remove the plastic end off the core. I unthread the brass body off of the cable, then go back down to the drive and pull the entire core out of the cable by pulling on square shift plunger.
I loosen the Bellow hose clamp off of the gimbal housing. I tie a string to the end of the shift cable sheath up by the engine, turn the outdrive full port, then pull the sheath and bellow out of the gimbal housing.
Untie the pull string, mark the sheath where the old bellow was, remove the old bellow. Use plenty of lube on the new bellow and work it into the sheath stopping at the mark. Tie on the string. Have someone pull the String while you guide it through the gimbal housing. I use black RTV on the flange, then slip the bellow onto the flange, tighten the hose clamp, snug. Put the shift cable back together. Use two wire ties to secure the bellow to the shift cable. You will need to perform a shift cable adjustment procedure once completed.
I use this method instead of loosening the nut securing the cable In the bell housing. That nut can sometimes be seized, and if it breaks the end of the cable sheath, it’s game over.....time for a new shift cable.
good luck.
