[flybouy]

I have a Flojet that I bought 15 years ago. At that time we had a 29' ultralight that sat low so many cg sewer outlets were higher than the discharge. With 2 teenage daughters at the time who often brought friends along, the pump would get hair accumulated around the impeller. I used a pair of extra long needle nose pliers from HF to remove it. The one I have has a plastic case for storage and a water connection to rinse.
Lots of water is essential. For these reasons I would not recommend tank mounting one. The one I have will pump out the tank in a few minutes. It does use lot's of power so good, charged battery is essential, think about running a starter motor for 5-10 straight (same type permanent magnet motor. I used two 3/4" dedicated hoses, one to drain and one to rinse that were gray and black in color so I wouldn't mix them up.
Good luck with your project.