If you look at the floor behind your motor box you will see that it is a section. Two ways to take it out. 1. Unscrew the hinges on the motor box and then there should be 4-6 screws which attach the floor to the boat. Lift out floor section. 2. Leave motor box attached and just undo the floor screw, and take out the floor and motor box as one section (two people may be needed for this approach.
On mine, I also had to remove the rear seat and also the vertical piece in front of the gas tank to get back far enough to remove the blower hose.
You could also do what I did for a season, which was to cut out the damaged section of blower hose and duct tape in a piece of expandable dryer vent hose to seal up the two sections.
1996 Prostar 190, 350 TBI and Powerslot