Shifter cable boot

[Logan1500]

I just got back from the river for the first trip out in my recently purchased used boat. (Seems like I keep finding issues!)

I have a 1985 Larson with an inboard 3.0 Mercruiser and an Alpha One outdrive.

I was taking on water back by the stern. I tracked it down to a a rubber boot which I beleive is around the shifter cable. There are three rubber boots back there and this one is the smallest one.

Can someone please let me know how hard these are to change out and what I have to do to do this? Would I be better off to take it to the dealer? I do have a general knowledge of working mechanics and have access to mechanics.

Thanks for your time.

John S.