Adding a Ballast System in Ski Locker

During the "off season" I am going to add a ballast tank to the ski locker in my Mobius LS. My plan is "T" off the existing pump in the engine compartment to go to the ski locker and then "T" into the bilge pump line to pump the water out.

My question to those who have the ballast system in the ski locker is how do you get the 2 lines (in and out) from the engine compartment to the ski locker? I believe there is an existing hole with some sort of plastic piece in the hole, do you use this or drill new holes? Needless to say, I am very nervous about drilling holes in my boat.

Thanks

AZ_Calling, It is just a plastic tub that lines the ski locker, you can pop right through it with a hole saw. Follow your battery cables it should give you an idea of what you are dealing with.

Good luck,E