Try this instead of cutting...
If you can get to it to cut it, you should be able to get it off and get the new hose onto it. Warm the hose with a blow dryer (after you've loosened the hose clamps of course). Since you're removing it permanently, don't worry about overheating it...you want to soften it up enough to be able to pull it off. When you put the new hose on, slide the hose clamps onto it first...doesn't matter if they slide all the way down to the tank, you just want to have 'em around the hose. Warm the hose with a blow dryer--carefully this time...put a little K-Y jelly on the inside of the hose and on the pumpout fitting, and you should be able to get the hose onto it without too much gruntin', groanin' and strained muscles. If not, Plan B should be: remove the deck fitting...push the hose all the way through the hole...slip the hose clamps on the fitting so all you have to do is position and tighten 'em later...and put it on the fitting while it's out. Then put the deck fitting back and re-bed it use Life Caulk or something similar...don't even THINK of using 5200.
