We have a 2002 Islander 270.
I initially installed a Simrad AP-12H. Upgraded last year to an AP-16VF.
You might as well "T" in to the two lines right at the back of the helm, because you have to connect a third line to the "return" on the helm - the connection that currently has a plug in it.
I mounted the pump in the compartment at the aft end of the starboard V-berth. Same compartment as the trim tab pump. It is a good location because the pump can be noisy, but it is a chore to run the three hydraulic lines up there behind the built-ins in the head.
You could look for a location at the stern for the pump, but then you have long hydraulic and power runs.
I made the mistake of using pre-fab Seastar hose sections. They are much stouter than needed. You can make your own as you go, with the correct cutter.
The compass for the AP-12H was originally on the aft side of the bulkhead between the cabin and the bridge. I actually installed it through the small inspection port at the forward end of the bridge deck. When I upgraded to the AP-16, I had to move the compass to the forward face of the bulkhead at the aft section of the bridge area - again mounted through the small inspection port.
The computer for the AP-16 is in the head, on the aft face of the forward bulkhead, just below the angled section above the toilet.
The control head is mounted on the helm area.
If you are not using virtual feedback, then you will need to run the cable for the rudder sensor from aft to the computer.
Please feel free to contact me if you want to set up a phoncon. I have done a few other installations, in addition to the two on our boat.
Brian
P.S. The 150-gal tank fills the entire area under the hatch on our boat. You don't want to put anything there.
