Changing the alternator belt

by Bruce Rogers
(Ferris,tx. U S A)

That sounds easy but it is on a 98 Bayliner with a General Motors in-line four-cylinder 3 L motor.

The water pump pulley is so close to the front motor mount bolt that there is no room to slip the belt out and change it.
There is a bracket on the front of the motor that is attached to the front motor mount with a bolt located at the bottom of the pulley and just a little bit forward, probably to give enough room to put a wrench on the boat to secure the front motor to the engine mount. There is not enough room between the bolt and the pulley to get the alternator belt out.
If I need to remove the water pump pulley I can do that but how do I keep the pulley from rotating when I try to take that last bolt out?
I could supply a picture but it's dark right now but maybe I explained it clear enough that a picture won't be necessary.
I'm not looking to try and get the engine out of alignment getting that belt off anyway it's just driving me crazy that I'm not able to figure out how to get it off.
This webpage is demanding that I include a picture or I cannot submit my question to you so I am just going to add a picture that I took to satisfy the requirements to submit my question to you. I tried sending a video earlier but it would not accept the video.