I just did the hoses on my boat this weekend. I am still bruised and have more cuts and scraps on my hands and arms, then I care to think about. Over all the job was not to bad, it took me about 3 hours, I had to drill to 5' holes in the cabin deck. Regal was nice enough to put to 90 degree bends back to back, thru 2 holes in hte bulk heads, that were only big enough to get the hoses thru. Once I drill the holes, it worked out ok. The other problem I had, was the fittings they used were the grey PVC fittings, and the new hose did not fit on to well. even with boiling the ends of the hose, I could only gedt it on abot 3/8 of an inch. I will have to get new nylon fittings, and replace the ones that were there. ( I had to get the head working again, the family was on there way to the boat.)
Two pieces of advice, First make sure you can fish the hose thru with out connecting it to the old fitting and pulling it thru. There may be a bend or a hole that you can not get the fitting thru. Second, make sure you empty and flush the holding tank first. I emptied the tank then filled it with fresh water 3 times before I unhooked any hose. when you are flushing the tank out, make sure you flush the toliet several times, so the line from the toilet to the tank only has fresh water in it.