I replaced bilge hose on H34 too.
But I did it when my floor was ripped up. You have a 3/4 inch hose now - I changed mine to a 1-1/8. A check valve is necessary to prevent cycling of the pump because of all the backflow. You have about 10+ ft of hose you'll have to run.The only problem you may have is under the floor. If the hose moves freely between the bilge and the floor exit right next to the water heater, it won't be too difficult. If it does not move freely, you are in for some FUN!The best way to get a new hose in under your situation is to get a male/male barb and attach it between the old hose and new hose. Then wrap electrical tape between the old and new hose and cover at least 3-6 inches on both hoses. You never want the two hoses to come detatched while under the floor or you are in for FUN * 1000.Use a push pull technique - this requires an assistant. Go back and forth in a rocking motion and twist clockwise from the bilge end if it has a sticking point.Once your past the floor it is just awkward. There are wire ties behind the stove and under the kitchen top and this is just a pain to get to. Oh, and once you get past the galley, you have to crawl into the starboard lazarette to attach the new hose to the thru hull.Good luck.