I am not a flush-pro fan as I also had problems with a cracked housing. I use a very simple mercruiser system that works great. http://www.michiganmotorz.com/mercru...sh-p-3334.html
I got mine at boat house discount marine for half the price listed in the link. The T fitting is metal and goes in just before the raw water pump and shoots the water up into the pump. When you are done flushing and turn the motor off the water back flows through the tranny cooler and flushes any weeds back out the intake. I mounted the fitting right next to the ski pole under the engine cover. The valve opens when you connect the male and female ends together. I leave the hose turned on all the time at my dock and just pull into the boat lift, raise the engine cover and plug the fittings together to start the water flow. By the time I lift the still running boat out of the water and do a clean up the engine is done flushing. I then turn the motor off and let the water back flow out the tranny cooler for a minute or so.
Crappy picture of the mounting but just above my thumb you can see where I mounted the female valve fitting with the supplied mounting bracket. The large metal pipe fitting is simply spliced in between the tranny cooler and the raw water pump.
You are missing some excellent late season weather. A shorty wet suit and 80 degrees had me out all weekend with my other two ski buddy neighbors.