Windshield wiper motor replacement

The starboard wiper motor is not moving. Is there a module to check first. The motor does not even try to move so I do not think it is a mechanical issue.
Secondly, changing will be a challenge. Access is through the speaker and my hand just reaches it. My guess is the top of the motor was heavily siliconed then the drive shaft was pushed through the hull and bolted from the deck. Getting the silicone detached seems impossible from two feet away through a small opening.

Has anyone done this before?

Any advice is welcome.
Jim