Mine are located on the transom - port side behind a false wall. I would think 1.5" hoses would be a huge pain in the ass to plumb looking at the cluster fudge I have with 6 one inch hoses in that tight space. I have one pump straight up, one upside down and one sideways for hose configuration but still easy enough to check the impellers.

When I drain my built in cooler, it pours out directly into bilge next to the the thru hull intakes. We go through 50-70 pounds of ice a weekend which ultimately gets drained while sitting on lift at end of day. I would not want my Jabsco pumps in bilge area but I understand the dilemma.

The only area I don't really use in my boat is underneath the rear center seat. It contains another white plastic cooler which is removable to access the Vdrive and tranny. I store my surf ropes in there but not really great usable space otherwise. Not sure if your '05 24SSV is similar to my 242 but if I had to mount pumps and keep them close to the hull, I'd figure out a way to use that space as it centers between the two lockers and easy access to front bag possibly.

If you want to spend more money, remove the muffler if similar to the pic MJHKnox, use straight pipes and add on FAE and you will gain space in front of motor if needed.