Ian I tried the what you are talking about and the water doesn't flow back so easy, that is why I did the extra empty pump.

Jester those are the factory 3/4" solenoids. Tell you the truth about the discharge pump I have no idea what kind it is. I found it @ salvation army for $5. It had a crack in the housing that someone tried to epoxy and it didn't work. I cleaned all the epoxy off and re-epoxyed the housing correctly. I believe its a 900 gph. I see that pump with hoses on ebay all the time sold as a ballast kit.

Wakeboard89 I used a second Rule live well pump wired up to the existing factory rule live well pump.
Yes it is all flip of a switch. The only electrical changes I made was splice the second fill pump into the original. So when I turn 1 on they both turn on.
The new bow discharge pump still has the cigarette lighter plug which I have hidden and have laying right next to the outlet near the drivers seat. I didn't want to put any perminent switches in until I knoew everything is proven and works efficiently.