Are you sure the macerator has failed?
That you don't just have a blocked tank vent that's causing the macerator to pull a vacuum till it overheats and shuts off? If the motor runs, but it's not pumping anything out, the problem is most likely just a fried (from running dry) or worn out impeller. If there's a y-valve in the pumpout line (if not, now you know why there should be...not just a tee fitting), close it, put a pan under the hose connection to catch the small spill of waste that'll be in the hose between the y-valve and macerator pump...remove the macerator and replace the impeller. Even without a y-valve, if you can aim the hoses up, you should be able to get the macerator out without a major spill...though it may be a two person job. However...I don't know how you could legally be using the macerator in the first place..'cuz you'd have to be at sea at least 3 miles offshore from the EAST of Long Island to use it legally...which is a long trip from anywhere in CT...one I doubt you're making just empty a tank.