Tex
You should have an inspection plate under the console. The fuel line should be accessible inside. Generally it's secured with two hose clamps but because of the age, you might have to cut the line off. I would secure the "New Fuel Hose" to the old at the engine. Then pull the "Old Fuel Hose" thru the inspection plate with the new line following thru in tow.(a little Vasoline on the line helps.) Hopefully the line is free and not jammed up or secured with tight hose clamps along the way, whereas you might have to remove the deck hatch
Good Luck